1. Paul’s Distinction Between the Old and New Man
The Apostle Paul’s distinction between the “old man” (ho palaios anthropos) and the “new man” (ho neos anthropos) provides a foundational framework for understanding Christian transformation. The old man signifies the self enslaved by sin, habitual desires, and attachments, whereas the new man is the self renewed in Christ through the Spirit, capable of holiness and divine knowledge. Yet while Paul emphasises the transformation effected by the Spirit, his language leaves room for further exploration. St. John of the Cross, drawing upon Pauline theology, penetrates deeper into the subtlety and radicality of this transformation, offering a profound account of the purification required for the new man to emerge fully in the believer’s soul.
Paul’s distinction has been interpreted in multiple complementary ways. Morally and ethically, the old man represents the pre-conversion self dominated by sin and habitual vices, while the new man is renewed by the Spirit and capable of holiness and obedience. Ontologically, the old man signifies humanity in its fallen, Adamic state, whereas the new man is the new creation in Christ, the renewal of the divine image, indicating a fundamental re-creation rather than mere ethical improvement. Psychologically, the old man denotes lingering sinful tendencies even after conversion, while the new man reflects the believer’s true self in union with Christ, cultivated through conscious cooperation with God’s grace. Communally, the old man corresponds to pre-Christian social patterns or life under the law, and the new man embodies the believer’s identity within the body of Christ, highlighting that spiritual transformation reshapes not only the individual but the Church as a whole. Spiritually and mystically, the old man is enslaved by attachments and passions, whereas the new man is vivified by the Spirit, capable of profound union with God, a transformation marked sacramentally in baptism and progressively realised through the interior life.
2. Circumcision and Purification: Physical and Spiritual
In Paul’s thought, circumcision serves both a physical and spiritual function. Physical circumcision, the mark of the covenant in Israel, distinguished God’s people externally and symbolised purity, dedication, and separation to God. Paul, however, shifts the focus to spiritual circumcision of the heart, effected by the Spirit rather than by the flesh. This inward circumcision transforms desires, affections, and motives, aligning them with God’s will and allowing participation in divine life.
The notion of circumcision of the heart is already present in the Old Testament, notably in Deuteronomy 10:16(“Circumcise therefore the foreskin of your heart, and be no longer stubborn”) and Jeremiah 4:4 (“Circumcise yourselves to the Lord, and remove the foreskin of your hearts”). Spiritual circumcision purifies the heart, enabling worship “from above” rather than merely external ritual compliance, and opens the path to knowing Christ in a divine, participatory way. It is through this inward purification that one can truly put on the new man, live according to the Spirit, and bear the fruits of holiness in both thought and action. The believer is thus marked not by fleshly credentials or external observance, but by a heart conformed to Christ, fully incorporated into God’s covenantal life and empowered for spiritual discernment and ethical transformation. (see also here)
3. The Sermon on the Mount and Spiritual Readiness
The ethical demands of the Sermon on the Mount presuppose a prior circumcision of the heart. Without inward purification by the Holy Spirit, the believer cannot genuinely fulfil Christ’s commands, such as loving one’s enemies, turning the other cheek, or praying for persecutors. If the heart remains untransformed, the new man exists only in potential; it is still embryonic, incapable of concrete expression in daily life. Spiritual circumcision opens the interior space in which the new man can function: only a heart renewed “from above” can live the beatitudes and enact the radical ethics of Christ’s new law. Ethical perfection is not merely a matter of effort or external observance, but the fruit of divine transformation.
4. The New Law as the Holy Spirit in the Heart
For Paul, the new law is not an external code but the indwelling Holy Spirit, who purifies the heart and moves the believer to enact God’s will. Spiritual circumcision is the essential preparation: the Spirit circumcises the heart, freeing it from selfish desires and aligning it with God’s love. The believer, now clothed with the new man, is able to put into practice the law of Christ, fully expressed in the Sermon on the Mount. Obedience and ethical formation arise from the Spirit’s transformative presence within, enabling the believer to live in harmony with the divine will and to manifest the love and righteousness that the law truly requires.
5. Johannine Parallels: Flesh and Spirit, From Above and From Below
John’s Gospel employs related concepts, particularly flesh versus Spirit and from above versus from below, which parallel Paul’s framework but differ in emphasis. Flesh refers to human limitation, weakness, or dependence on worldly standards, while Spirit signifies divine life enabling rebirth and eternal life. “From above” denotes divine origin, the Spirit, and eternal life, while “from below” signifies human, worldly existence. Paul’s old/new man corresponds to John’s flesh/Spirit and from above/from below motifs: the old man and human knowledge correspond to flesh and life from below, whereas the new man and divine knowledge correspond to Spirit and life from above.
6. Clothing Imagery and Habitual Transformation
Paul frequently uses clothing imagery to illustrate transformation. Being “clothed with Christ” is both ontological and habitual: Romans 13:14 exhorts believers to “put on the Lord Jesus Christ,” Galatians 3:27 presents baptism as putting on Christ, and Ephesians 4:22–24 and Colossians 3:9–10 emphasise putting on the new man in an ongoing process that combines interior renewal with ethical practice. Clothing conveys union with Christ, habitual moral formation, protection, and identity. It complements the old/new man imagery: one removes the old self and dons the new self, wearing Christ’s virtues as a living reality.
7. Human and Divine Knowledge of Christ
Paul distinguishes between knowing Christ humanly and divinely, particularly in 2 Corinthians 5:16. Human knowledge is limited, superficial, or historical, whereas divine knowledge is relational, participatory, and Spirit-enabled. Beginners may know Christ outwardly, while advanced believers know him intimately and transformatively. Both Paul and Hebrews use food imagery to differentiate spiritual stages: milk for foundational teaching accessible to beginners, solid food for deeper wisdom for the mature. The capacity to digest spiritual truths depends on habitual practice and the Spirit’s guidance, allowing the new man to flourish in ethical, cognitive, and mystical dimensions.
8. St. John of the Cross: Radical Interior Purification
St. John of the Cross deepens the Pauline vision by emphasising the radical interiority of transformation. He asserts that true renewal requires purification of the roots of action, the habitual tendencies and inclinations that generate behaviour. The old man persists not only in acts but in the dispositions shaping the soul. The Holy Spirit’s work penetrates these depths gradually, as only God can effect such profound interior transformation. St. John identifies two stages: first, purification from the slavery of sensuality and attachment, freeing the soul from bodily and worldly dominion; second, purification of the spirit itself, uprooting residual tendencies of the old man and perfecting the new man at its core. This process renders the soul capable of profound union with God, authentic worship, and faithful exercise of the law of Christ.
In this mystical perspective, the emergence of the new man is both gift and labour. Human collaboration is indispensable, yet the deepest purification cannot be accomplished without God’s direct action. The old man’s remaining tendencies serve as the soil in which the soul learns to surrender, receive, and be transformed by the Spirit. The new man, fully clothed in Christ and purified at its roots, is not merely an ethical ideal but a living reality: it enables divine knowledge, authentic love, and faithful practice of God’s will. Transformation is holistic, encompassing acts, habits, and the spirit itself, progressively realised through the Spirit’s indwelling presence, and culminating in full participation in divine life.
9. Integrating Pauline and Carmelite Perspectives
The integration of Pauline and Carmelite perspectives offers a comprehensive understanding of spiritual transformation. Paul provides the theological foundation, outlining the transition from the old man to the new man through union with Christ and the indwelling of the Holy Spirit. St. John of the Cross deepens this understanding by highlighting the necessity of radical interior purification, addressing not only external behaviors but also the internal dispositions that shape them.
Together, these perspectives underscore that spiritual transformation is both a gift of God’s grace and a process requiring the believer’s active cooperation. It involves a deep purification of the heart, enabling the believer to live authentically according to the new law—the law of the Spirit—and to manifest the love and righteousness exemplified in the Sermon on the Mount.
Texts From St. John of the Cross
Text 1
“The soul cannot come to this union without great purity, and this purity is not gained without great detachment [desnudez] from every created thing and vigorous mortification. This is signified by the stripping of the Bride of her mantle and by her being wounded by night as she sought and went after the Spouse; for the new mantle which belonged to the betrothal could not be put on until the old mantle was stripped off. Wherefore, he that refuses to go forth in the night aforementioned to seek the Beloved, and to be stripped [desnudado] of his own will and to be mortified, but seeks Him upon his bed and at his own convenience, as did the Bride, [Songs 3:1] will not succeed in finding Him. For this soul says of itself that it found Him by going forth in the dark and with yearnings of love.” (Dark Night II, 24,4)
Text 2
[A Question]
4. But there is a question [duda] which at once arises here — namely, since the things of God are of themselves profitable to the soul and bring it gain and security, why does God, in this night, darken the desires and faculties with respect to these good things likewise, in such a way that the soul can no more taste of them or busy itself with them than with these other things, and indeed in some ways can do so less?
[Answer]
The answer is that it is well for the soul to perform no operation touching spiritual things at that time and to have no pleasure in such things, because its faculties and desires are base, impure and wholly natural; and thus, although these faculties be given the desire and interest in things supernatural and Divine, they could not receive them save after a base and a natural manner, exactly in their own fashion. For, as the philosopher says, whatsoever is received comes to him that receives it after the manner of the recipient. [1] Wherefore, since these natural faculties have neither purity nor strength nor capacity to receive and taste things that are supernatural after the manner of those things, which manner is Divine, but can do so only after their own manner, which is human and base, as we have said, it is meet that its faculties be in darkness concerning these Divine things likewise.
Thus, being weaned and purged and annihilated in this respect first of all, they may lose that base and human way of receiving and acting, and thus all these faculties and desires of the soul may come to be prepared and tempered in such a way as to be able to receive, feel and taste that which is Divine and supernatural after a sublime and lofty manner, which is impossible if the old man die not first of all.
5. Hence it follows that all spiritual things, if they come not from above and be not communicated by the Father of lights to human desire and free will (howsoever much a man may exercise his taste and faculties for God, and howsoever much it may seem to the faculties that they are experiencing these things), will not be experienced after a Divine and spiritual manner, but after a human and natural manner, just as other things are experienced, for spiritual blessings [bienes] go not from man to God, but come from God to man. With respect to this (if this were the proper place for it) we might here explain how there are many persons whose many tastes and affections and the operations of whose faculties are fixed upon God or upon spiritual things, and who may perhaps think that this is supernatural and spiritual, when it is perhaps no more than the most human and natural desires and actions. They regard these good things with the same disposition as they have for other things, by means of a certain natural facility which they possess for directing their desires and faculties to anything whatever.
6. If perchance we find occasion elsewhere in this book, we shall treat of this, describing certain signs which indicate when the interior actions and motions of the soul, with respect to communion with God, are only natural, when they are spiritual, and when they are both natural and spiritual. It suffices for us here to know that, in order that the interior motions and acts of the soul may come to be moved by God divinely, they must first be darkened and put to sleep and hushed to rest naturally as touching all their capacity and operation, until they have no more strength.
7. Therefore, O spiritual soul, when you see your desire obscured, your affections arid and constrained, and your faculties bereft of their capacity for any interior exercise, be not afflicted by this, but rather consider it a great happiness, since God is freeing thee from thyself and taking the matter from thy hands. For with those hands, howsoever well they may serve thee, thou wouldst never labour so effectively, so perfectly and so securely (because of their clumsiness and uncleanness) as now, when God takes thy hand and guides thee in the darkness, as though thou wert blind, to an end and by a way which thou knowest not. Nor could you ever hope to travel with the aid of thine own eyes and feet, howsoever good thou be as a walker.
8. The reason, again, why the soul not only travels securely, when it travels thus in the darkness, but also achieves even greater gain and progress, is that usually, when the soul is receiving fresh advantage and profit, this comes by a way that it least understands–indeed, it quite commonly believes that it is losing ground. For, as it has never experienced this newness feeling which drives it forth and dazzles it and makes it depart recklessly from its former way of life [su primer modo de proceder], it thinks itself to be losing ground rather than gaining and progressing, since it sees that it is losing with respect to that which it knew and enjoyed, and is going by a way which it knows not and wherein it finds no enjoyment.” (Dark Night II, 16,4ss)
[1] Parallel texts: Ascent II,29,6; 1DN 4,2 e LF 3,34. This profound and important principle, which has often been developed in mystical theology, is well expounded by P. José de Jesús María in a treatise called Reply to a question [Respuesta a una duda]. Here, among other things, he says: ‘As St. Thomas proves (De Veritate, q. 12, a. 6), Divine illumination, like every other spiritual form, is communicated to the soul after the manner of the receiver of it, whether according to sense or according to spirit, to the particular or to the universal. And thus, he that receives it must prepare himself for it to be communicated to him further, whether in small measure (as we say) or according to sense, or in large measure or intellectually.’ “Quidquid recipitur ad modum recipientis recipitur”. “For to him who has will more be given, and he will have abundance; but from him who has not, even what he has will be taken away.” (Matthew 13:11–12) “You will get the God you want” (Therese to a nun). Severe, etc. Rigidity prevents change, hinders God’s action in us.
The Philosopher is Aristotles who is attributed the moto/maxim, used in a simplified form: « Quidquid recipitur, ad modum recipientis recipitur » (De anima, l. III, c. 4, lect. 8; cit. in S Th I, q. 79, a. 6c). In Living Flame B 3,34, saint John of the Cross attributes the maxim in a generic way “as the philosophers say”. With the mystical doctor it assumes the value of a axiom which regards the human behaviour in front of God. God communicates himself to the beginners in a different way compared to the one used with the perfects. But this means that the human being needs to perceive the turning points in God’s way of communicating himself and adapt himself to the new way God communicates himself.
Text 3
Ascent of Mount Carmel, Chapter V
Wherein is described what is meant by union of the soul with God. A comparison is given.[1]
1. FROM what has been said above it becomes clear to some extent what we mean by union of the soul with God; what we now say about it, therefore, will be the better understood. It is not my intention here to treat of the divisions of this union, nor of its parts, for I should never end if I were to begin now to explain what is the nature of union of the understanding [mind], and what is that of union according to the will, and likewise according to the memory; and likewise what is transitory and what permanent in [the union of] the said faculties; and then what is meant by total union, transitory and permanent, with regard to the said faculties all together. All this we shall treat gradually in our discourse – speaking first of one and then of another. But here this is not to the point in order to describe what we have to say concerning them; it will be explained much more fittingly in its place, when we shall again be treating the same matter, and shall have a striking illustration to add to the present explanation, so that everything will then be considered and explained and we shall judge of it better.
2. Here I treat only of this permanent and total union according to the substance of the soul and its faculties with respect to the obscure habit of union: for with respect to the act, we shall explain later, with the Divine favour, how there can be no permanent union in the faculties, in this life, but a transitory union only.
3. In order, then, to understand what is meant by this union whereof we are treating, it must be known that [see other passages] God dwells and is present substantially in every soul, even in that of the greatest sinner in the world. And this kind of union is ever wrought between God and all the creatures, for in it He is preserving their being: if union of this kind were to fail them, they would at once become annihilated and would cease to be. And so, when we speak of union of the soul with God, we speak not of this substantial union which is continually being wrought, but of the union and transformation of the soul with God, which is not being wrought continually, but only when there is produced that likeness that comes from love; we shall therefore term this the union of likeness, even as that other union is called substantial or essential. The former is natural, the latter supernatural. And the latter comes to pass when the two wills — namely that of the soul and that of God — are conformed together in one, and there is naught in the one that repugnant to the other. And thus, when the soul rids itself totally of that which is repugnant to the Divine will and conforms not with it, it is transformed in God through love.
4. This is to be understood of that which is repugnant, not only in action, but likewise in habit, so that not only must the voluntary acts of imperfection cease, but the habits of any such imperfections must be annihilated. And since no creature whatsoever, and none of its actions or abilities, can conform or can attain to that which is God, therefore must the soul be stripped [desnudar] of all things created, and of its own actions and abilities – namely, of its mind, perception [understanding, perceiving] and feeling – so that, when all that is unlike God and unconformed [disconforme] to Him is cast out, the soul may receive the likeness of God; and nothing will then remain in it that is not the will of God and it [its spirit] will thus be transformed in God. Wherefore, although it is true that, as we have said, God is ever in the soul, giving it, and through His presence conserving within it, its natural being, yet He does not always communicate supernatural being to it. For this is communicated only by love and grace, which not all souls possess; and all those that possess it have it not in the same degree; for some have attained more degrees of love and others fewer. Wherefore God communicates Himself most to that soul that has progressed farthest in love; namely, that has its will in closest conformity with the will of God. And the soul that has attained complete conformity and likeness of will is totally united and transformed in God supernaturally.
[old man, wrapped, desnudez,…]
Wherefore, as has already been explained, the more completely a soul is clothed with [vestida] in the creatures and in its own abilities, by habit and affection, the less preparation [disposition] it has for such union; for it gives not God a complete opportunity to transform it supernaturally. The soul, then, needs only to strip itself [desnudarse] of these natural dissimilarities and contrarieties, so that God, Who is communicating Himself naturally to it, according to the course of nature, may communicate Himself to it supernaturally, by means of grace.
5. And it is this that Saint John desired to explain when he said: Qui non ex sanguinibus, neque ex voluntate carnis, neque ex voluntate viri, sed ex Deo nati sunt. [John 1:13] As though he had said: He gave power to be sons of God — that is, to be transformed in God — only to those who are born, not of blood — that is, not of natural constitution and temperament — neither of the will of the flesh — that is, of the free will of natural capacity and ability — still less of the will of man — wherein is included every way [modo] and manner of judging and comprehending with the mind.
He gave power to none of these to become sons of God, but only to those that are born of God — that is, to those who, being born again through grace, and dying first of all to everything that is of the old man [Eph 4:22], are raised above themselves to the supernatural, and receive from God this rebirth and adoption, which transcends all that can be imagined. [clearly not directly the Baptism]
For, as Saint John himself says elsewhere: Nisi quis renatus fuerit ex aqua, et Spiritu Sancto, non potest videre regnum Dei. [John 3:5] This signifies: He that is not born again in the Holy Spirit will not be able to see this kingdom of God, which is the state of perfection [clearly not directly the Baptism]; and to be born again in the Holy Spirit in this life is to have a soul most like to God in purity, having in itself no admixture of imperfection, so that pure transformation can be wrought in it through participation of union, albeit not essentially.
6. In order that both these things may be the better understood, let us make a comparison. A ray of sunlight is striking a window. If the window is in any way stained or misty, the sun’s ray will be unable to illumine it and transform it into its own light, totally, as it would if it were clean of all these things, and pure [sencilla]; but it will illumine it to a lesser degree, in proportion as it is less free from those mists and stains; and will do so to a greater degree, in proportion as it is cleaner from them, and this will not be because of the sun’s ray, but because of itself; so much so that, if it be wholly pure and clean, the ray of sunlight will transform it and illumine it in such wise that it will itself seem to be a ray and will give the same light as the ray. Although in reality the window has a nature distinct from that of the ray itself, however much it may resemble it, yet we may say that that window is a ray of the sun or is Light by participation. And the soul is like this window, whereupon is ever beating (or, to express it better, wherein is ever dwelling) this Divine light of the Being of God according to nature, which we have described.
7. In thus allowing God to work in it, the soul (having rid itself of every mist and stain of the creatures, which consists in having its will perfectly united with that of God, for to love is to labour to detach and strip itself for God’s sake of all that is not God) is at once illumined and transformed in God, and God communicates to it His supernatural Being, in such wise that it appears to be God Himself, and has all that God Himself has. And this union comes to pass when God grants the soul this supernatural favour, that all the things of God and the soul are one in participant transformation; and the soul seems to be God rather than a soul, and is indeed God by participation; although it is true that its natural being, though thus transformed, is as distinct from the Being of God as it was before, even as the window has likewise a nature distinct from that of the ray, though the ray gives it brightness.
8. This makes it clearer that the preparation [dispocision] of the soul for this union, as we said, is not that it should understand or perceive or feel or imagine anything, concerning either God or aught else, but that it should have purity and love — that is, perfect detachment [desnudez] and resignation from everything [de lo uno y de lo otro] for God’s sake alone; and, as there can be no perfect transformation if there be not perfect purity, and as the enlightenment, illumination and union of the soul with God will be according to the proportion of its purity, in greater or in less degree; yet the soul will not be perfect, as I say, if it be not wholly perfect and bright and clean.
9. This will likewise be understood by the following comparison. A picture is truly perfect, with many and most sublime beauties and delicate and subtle illuminations, and some of its beauties are so fine and subtle that they cannot be completely realised, because of their delicacy and excellence. Fewer beauties and less delicacy will be seen in this picture by one whose vision is less clear and refined [purificada]; and he whose vision is somewhat more refined [pura] will be able to see in it more beauties and perfections; and, if another person has a vision still more refined [pura], he will see still more perfection; and, finally, he who has the clearest and purest [cleanest] faculties will see the most beauties and perfections of all; for there is so much to see in the picture that, however far one may attain, there will ever remain higher degrees of attainment.
10. After the same manner we may describe the condition of the soul with relation to God in this enlightenment or transformation. For, although it is true that a soul, according to its greater or lesser capacity, may have attained to union, yet not all do so in an equal degree, for this depends upon what the Lord is pleased to grant to each one. It is in this way that souls see God in Heaven; some more, some less; but all see Him, and all are content, for their capacity is satisfied.
11. Wherefore, although in this life here below we find certain souls enjoying equal peace and tranquillity in the state of perfection, and each one of them satisfied, yet some of them may be many degrees higher than others. All, however, will be equally satisfied, because the capacity of each one is satisfied. But the soul that attains not to such a measure of purity as is in conformity with its capacity never attains true peace and satisfaction, since it has not attained to the possession of that detachment [desnudez] and emptiness in its faculties which is required for simple union.
[1] As the Saint has explained above, this is a parenthetical chapter necessary to an understanding of the following chapters on the active purification of the three faculties of the soul; for, in order to make an intelligent use of the means to an end, it is important to know what that end is. St. John of the Cross begins by setting aside the numerous divisions under which the mystics speak of union with God and deals only with that which most usually concerns the soul, namely union which is active, and acquired by our own efforts, together with the habitual aid of grace. This is the kind of union which is most suitably described in this treatise, which deals with the intense activity of the soul as regards the purgation of the senses and faculties as a necessary means for the loving transformation of the soul in God — the end and goal of all the Saint’s writings. In order to forestall any grossly erroneous pantheistic interpretations, we point out, with the author of the Médula Mística (Trat. V, Chap. i, No. 2), that by union the Saint understands ‘a linking and conjoining of two things which, though united, are still different, each, as St. Thomas teaches (Pt. III, q. 2, a. 1), keeping its own nature, for otherwise there would not be union but identity. Union of the soul with God, therefore, will be a linking and conjoining of the soul with God and of God with the soul, for the one cannot be united with the other if the other be not united with the one, so that the soul is still the soul and God is still God. But just as, when two things are united, the one which has the most power, virtue and activity communicates its properties to the other, just so, since God has greater strength, virtue and activity than the soul, He communicates His properties to it and makes it, as it were, deific, and leaves it, as it were, divinized, to a greater or a lesser degree, corresponding to the greater or the lesser degree of union between the two.’ This conception, which is a basic one in Christian mysticism, is that of St. John of the Cross. Had all his commentators understood that fact, some of them would have been saved from making ridiculous comparisons of him with Gnostics, Illuminists or even the Eastern seekers after Nirvana. Actually, this Saint and Doctor of the Church applies the tenets of Catholic theology to the union of the soul with God, presenting them in a condensed and vigorous form and keeping also to strict psychological truth, as in general do the other Spanish mystics. This is one of his greatest merits. In this chapter he is speaking, not of essential union, which has nothing to do with his subject, but (presupposing the union worked through sanctifying grace received in the substance of the soul, which is the source of the infused virtues, such as faith, hope and charity, and the gifts of the Holy Spirit) of active actual union, after which we can and should strive, so that we may will what God wills and abhor what He abhors. Though not the only kind of union, it is this which chiefly concerns the soul; and, when once this is attained, God readily grants all other mystical gifts. Cf. St. Teresa’s Interior Castle, V, iii [C.W.S.T.J., II, 259-60].
Read also:
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The Two Systems of Christian Life