This post is an excerpt from Theological Commonplaces: On Christ by Johann Gerhard.
§ 78. Thesis: In Christ there is a true, complete, and perfect human nature, and hence Christ also is a true, perfect, and natural man.
The explanation follows. By the “truth” of the human nature we understand that the Word did not assume an apparition or bare external appearance of a human nature, but became man in the truth of the fact. By the “completeness” of the human nature we understand that He assumed into the unity of His person all the essential parts of the human nature—not only the body but also the rational soul—because His flesh was ἔμψυχος σάρξ, flesh endowed with soul. We do not merely say that He was man but that He still is man, because what He once assumed He never put away nor will He ever put it away. He is said to be “true, perfect, and natural man” with regard to His essential and natural parts, though with regard to its origin (namely, its conception by the Holy Spirit) and with regard to its subsistence (namely, its assumption into the Word), His flesh is different than our flesh.
Proof of Christ's Humanity
§ 79. The one humanity of Christ is proved: (I) From titles, both proper and figurative …
(II) From the essential parts of man, which are the rational soul and the body …
(III) From the emotions that are proper to man, both those that befit the entire composite and those that belong to the individual parts of His soul and body. The Gospel bears witness that He was truly conceived and born; that He hungered, thirsted, became weary, walked from place to place, grew in age and wisdom, wept, was sad, exulted in the Spirit, etc.
** Some properties of the human nature are said according to itself [κατ’ αὐτό], and these befit the entire thing always; some are toward another [πρὸς ἕτερον], and these are said to be proper to Him only comparatively and with respect to something else. Belonging to this type are eating, drinking, sleeping, being hungry, suffering, etc. You see, though these are not in themselves proper to humanity—though by them the divine and human natures are distinguished and they cannot be attributed to the divinity of itself and in itself—they are called properties according to another [κατ’ ἄλλο]. **
(IV) From the proper works and effects of man, because not only in His state of humiliation does He understand, will, speak, preach, eat, drink, etc. (Acts 10:38ff. and ch. 13), but also in His state of exaltation He understands, wills, converses with the blessed angels and humans in His heavenly glory, etc. Several things were noticeable in Him: (1) The operations of natural life, which are proper to the nutritive faculty: He would hunger, thirst, eat, drink. (2) The operations of animal life, which are in the sensitive faculty: He would see, hear, and touch; or in the locomotive faculty: He would walk, stand up, lie down; or in the faculty of wrath and desire: He would rejoice, be affected by sadness, be angry, grieve, weep. (3) The operations of intellectual life [τοῦ διανοητικοῦ]: He would understand, reason, speak.
Christ as “the Son of Man”
§ 80. In regard to the first class of arguments, observe: (I) Christ is called “the Son of Man”: (1) Because of the prophetic title (Dan. 7:). As the title “Messiah,” taken from Daniel, was usual at that time, so also from the same prophet the Messiah was called “the Son of Man” by common custom. This Messiah was the one whom Daniel described in his prophetic vision.
(2) To prove His true humanity. Just as the only-Begotten was called “the Son of God” because He is true God, begotten of the Father from eternity, so also He is called “the Son of Man” and, indeed, “the firstborn” because in the fullness of time He, a true man, was born of the Virgin Mary.
(3) To prove His kinship with us. He could have been true man though not being a son of man, born from man, just as Adam was a true man, though he nevertheless was formed of the earth. Instead, He wanted to be born man of man and to become the Son of Man so that a bright testimony of His true humanity and of our kinship with Him might exist.
(4) Because of His emptying [exinanitio] and humiliation. Excellent men of outstanding authority are called … “the sons of a man [viri],” but commoners and obscure people are called … “the children of human beings [hominum].” Therefore such nomenclature leads us down to the humiliation of Christ, because of which, established as He was in the form of a servant, He calls Himself “the Son of Man [hominis].”
(5) Because of the administration of His office … in the days of His flesh, Christ calls Himself “the Son of Man” because He had been sent by God to man for man’s sake on account of the preaching of the Gospel and the redemption of the human race.
(6) To demonstrate His love. “His delight is with the sons of men” (Prov. 8:31). By this name, which is attributed to Him so often, He calls us back to consider His supreme love for mankind, because of which He wanted to become the “Son of Man."…
Use of the Word “Flesh”
§ 81. (II) The word “flesh” in John 1:14 is synecdochic and signifies the whole and perfect human nature, that is, the flesh endowed with a soul. … You see, from parallel passages that discuss the incarnation of the Son of God, we gather that it must be taken in this sense: (1) From the name “man,” which includes body and soul. (2) From the manner of our salvation, which required that Christ assume not only flesh but also a soul. (3) From the explicit mention of the rational soul, as we shall show more fully below.
The apostle wanted to use the word “flesh” in describing this mystery: (1) To show that the Word did not assume a person but a human nature, because the human nature that the Son of God assumed into the unity of His person was not previously a person subsisting of itself but was at the same time flesh, at the same time the flesh of the Word, at the same time flesh endowed with a soul.
(2) To teach that the Word did not assume an apparition or spiritual substance but the true human body consisting of flesh and bones, and therefore the true substance of the human nature, for in Luke 24:39 the spirit and the flesh are opposed to each other.
(3) To set forth for our consideration the immense love of the Son of God. Although by working without means He could have created for Himself a human nature far more happy and excellent than that which was in Adam before the fall, He preferred to assume a human nature that came from man, which, because of its frailty, wretchedness, and infirmities, is called “flesh,” yet without sin. (See Isa. 40:6; Ps. 78:39.)
(4) To set forth for our consideration the very intimate kinship and consanguinity by which the Son of God wished to be joined to us. This is usually described in Scripture in this way: “This is my bone and my flesh” (Gen. 2:23; 29:14; Judg. 9:2; 2 Sam. 5:1; Eph. 5:31; etc.).
From Theological Commonplaces: On Christ copyright © 2009 Concordia Publishing House. All rights reserved.