The Humanity of Christ 

The doctrine that the Lord Jesus had a true human body and a reasonable human soul:

He is called “the seed of the woman” (Gen. 3:15). He was of the seed of David (Rom. 1:3) and is emphatically called a man (1 Tim. 2:5). One of His titles is “the Son of Man” (Matt. 13:37, etc.).

1. He had a true human body. This was plainly laid down by the inspired apostles in opposition to some Gnostics,* the Docetae (see Docetism), who held that the body of Christ was merely a phantom and not real flesh and blood. Luke 24:39; John 20:27, and many other Scriptures destroy such a myth.

2. He had a reasonable soul. This contradicts the ancient heresy of Apollinarianism.* See Mt. 26:38; Mk. 6:6; Mt. 8:10; Luke 7:9. “Sorrow and wonder are rational emotions, proper to man, but not to God” (Shedd)—i.e., they are positive proof that the Lord Jesus had a true human soul.

It is interesting that while Lutheran theology emphasized the majesty of Christ’s humanity (see Lutheranism), Reformed theology stressed its reality. The Lutherans’ emphasis arises from their peculiar view of the Communicatio Idiomatum,* the idea that by the union of two natures in Christ His human nature was exalted by the communication of the properties of the divine. Why the communication should not also be of human properties to the divine nature is unclear. The axiom that the finite does not have the capacity to contain the infinite (finitum non capax infiniti) is ignored, with the result that “incarnation means not God becoming man, but man becoming God” (A. B. Bruce, The Humiliation of Christ, p. 108). Bruce goes on to charge that though the Formula of Concord* did not intend to do so, “the Lutheran Christology, to say the least, threatens the reality of Christ’s human nature with extinction” (idem).

The Reformed churches strongly opposed the Lutheran construction. They tried to do justice to the humiliation involved in the incarnation. It was an unspeakable act of self-humbling for the Son of God to enter into an irreversible union with a true human nature. So real was Christ’s humanity that during His earthly ministry, His deity was largely concealed under it. That is the real meaning of his kenosis.* He did not lose any of the properties of His essential deity; that was impossible. Rather, He laid aside the revelation or expression of them while He walked as a man among men.

Though rejecting the Lutheran view of Christ’s humanity, Reformed theology nevertheless sees it as a majestic humanity, majestic in its sinlessness as well as in the honour of being in personal union with the eternal Logos, majestic, as well, in the purposes for which God’s Son assumed our nature. Bruce summarized Ursinus’s statement of the Reformed construction of the doctrine:

“The eternal counsel of God for man’s salvation demanded that the Son of God should become Mediator and victim, reconciling us to the Father, and regenerating us into sons of God by the Holy Spirit. Therefore He assumed into the unity of His person a nature truly human, consisting of a rational soul and a human body, formed and sanctified by the power of His own Spirit in the womb of the Virgin, of the substance of His mother, joining and coupling it to Himself not only inseparably, but also by a secet and inscrutable vinculum [bond] in a most intimate and ineffable manner, so that the eternal Logos or Son of God, and this mass of the nature assumed, are at the same time the substance of the one person of Christ, who, one and the same, is true Son of God and true Son of man, true God and true man, born from eternity of the Father, and in time of the Virgin. In virtue of this union, divinity is not in Christ as in all creatures for their conservation and government; nor does it dwell in Him as in saints, making them conformable to Himself by grace and His own Spirit, but the Logos so inhabits and bears, moves and vivifies this His own flesh, that with it, once for all assumed into the unity of one person with Himself, He remains the hypostasis of one and the same person of Christ, as soul and body are so united by a secret inexplicable nexus [binding together] that they are substantial parts of one man, and the body would perish unless it were so borne by the soul; indeed, the Logos coheres with His flesh more closely than the soul with the body, so that even when His soul was separated from His body by death, He was not separated from either. On the other hand, while thus closely united, the natures are not changed or mixed or confused, but remain distinct while united, and retain their respective essential properties. Hence in the one person there is a twofold substance, essence, or nature; one divine, uncreated, creating, sustaining, and vivifying the other, spiritual, uncircumscribed, and always existing everywhere the same and whole; the other human, created, sustained, and vivified by the former, finite, corporeal, circumscribed by quantity and definite figure, having part beyond part, and existing only in one place at one time. Also a twofold mind or intellect; one divine and increate, knowing all things past, present, future, possible, impossible, from eternity to eternity, by itself, in one unchanging act or intuition, and the fountain of all creaturely intelligence; the other human, created, knowing and contemplating all things which it wishes to know, and when it wishes, through the divine mind united to it; able to perceive all sensible things by diverse, distinct acts of sensation and perception. Also a twofold will and operation; the one divine and increate, performing whatever it wishes, volens et nolens [purposing and not purposing], from eternity, immutably and in His own time, exciting the other and governing it at pleasure, as a part acting on another part of the one entire perfect Christ, the first cause of all His actions; the other human and created, ever agreeing with the divine, depending on it, willing and doing by its guidance whatever is its proper function. Also a twofold wisdom, strength, and virtue, one divine, increate, being the unique, total, most simple, infinite, and immutable essence of Deity; the other, human and created by the divine, itself neither the essence of Deity nor of humanity, nor even a thing subsisting by itself, but a quality and property produced in the human nature by the Logos through His own Spirit, and inhering therein as in its own subject, which grew in Christ humbled with His age, and in Christ glorified arrived at perfection; yet, while surpassing the gifts, comprehension, and intelligence of all men and angels, is nevertheless finite in the divine view, and can never be equal to the essential wisdom, power, and virtue of God; the finite to the infinite, the creature to the creator.

“In virtue of this union, whatever is said of Christ is said truly and really of His whole undivided Person, sometimes in respect of both natures, sometimes in respect of one or other. The former, when the predicate has reference to Christ’s office; He being Mediator, Redeemer, Intercessor, King, Priest, Prophet, in respect both to His Deity and to His humanity, and each nature performing its proper part in all official acts; the latter, when the predicate has reference to a peculiar property or operation of one of the natures. Thus it can be said that God was born, died, rose, ascended, but only in respect to the human nature of Christ; and again, that the man Christ Jesus is omnipotent, omniscent, omnipresent, in virtue, not of His humanity, but of His divinity. Yet in both cases the predication is not merely verbal, but real, in consequence of the union. It is the union which makes it proper to say, in the case of Christ, God suffered, the man Jesus is omniscient; while it would be improper to say of the Baptist, God suffered because he suffered, or the Baptist was omnipresent because God dwelt within him as well as without him.

“As to the distinction between the two states of humiliation and exaltation, it has a bearing on the properties of both natures, but in very different ways. With reference to the properties of the divine nature, it is a distinction simply between partial concealment and open manifestation. Christ in the state of humiliation had these properties not less than He has them now in glory; for they are His eternal and immutable divinity itself. He was then as omniscient, omnipotent, and omnipresent, as to His divinity, as now. But He did not manifest these properties then as now. He concealed His divinity in the state of exinanition,* and revealed it only in a modified manner, and so far as was needful for the office of that time. With reference to the properties of the human nature, on the other hand, the distinction between the states is more radical, implying for the state of exaltation the loss of some accidental properties possessed in the state of humiliation, the perfected development of others, and the retention of the essential properties. The accidental properties left behind by Christ, when He entered into glory, are the physical and mental infirmities which He assumed with humanity—liability to hunger, thirst, fatigue, grief, suffering, death, and ignorance. The properties in which He was perfected, also accidental, that is, not inseparable from the idea of human nature, are those of glory and majesty, as strength, agility, incorruptibility, brightness, wisdom, gladness, virtue. These Christ had in the state of humiliation, as far as was needful for His perfect purity and sanctity, and for the discharge of His office on earth; but in the state of exaltation He received such increase thereof, that, in the number and degree of His gifts, He far excels not only the highest excellence of angels and men, but even His own attainments in the days of His flesh” (ibid., pp. 118–121).

Thus, while maintaining the fundamentally important truth of Christ’s essential and eternal deity, Reformed theology glories in the humiliation of that deity in incarnation. In Christ there is a true union of a real human nature with the divine Son. The two natures remain unmixed and unconfused. The deity is not humanized and the humanity is not deified, as Lutheran Christology posits. By the act of incarnation, the Son of God took to Himself a human nature and will never revoke that act. He will retain His human nature forever.

The NT makes much of the truth of Christ’s real humanity and its union with His deity (John 1:14; Rom. 1:3–4; 9:5; 1 Tim. 3:16; Heb. 2:11–16). Indeed, it was a major burden of the apostles to refute all notions that His was not a real humanity. The epistles of John emphasize this with great incisiveness, asserting that he who denies that Jesus Christ has come in the flesh is antichrist (1 John 2:22; 4:3).

Since the assumption of humanity by the Son of God was His act in pursuance of His covenant engagement to be the mediator and redeemer of His people, it is natural that the impact of this doctrine should extend far beyond the establishment of an orthodox statement of faith to providing believers with a solid ground for their hope and comfort. As the Larger Catechism says, “It was requisite that the Mediator should be man, that he might advance our nature, perform obedience to the law, suffer and make intercession for us in our nature, have a fellow-feeling for our infirmities; that we might receive the adoption of sons, and have comfort and access with boldness to the throne of grace” (Question 39).

By the incarnation, “the Son of God became the Son of man in order that the sons of men might become the sons of God” (John Blanchard, Gathered Gold, p.162).


Cairns, A. (2002). In Dictionary of Theological Terms (pp. 214–217). Belfast; Greenville, SC: Ambassador Emerald International.

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