How can Jesus be God, when Numbers 23:19 says that God is not a man or a son of man?
The key to understanding Numbers 23:19 lies in grasping what the verse actually affirms and what the incarnation actually means.
What Numbers 23:19 Actually Says
Numbers 23:19 reads: "God is not a man, that He should lie; neither the son of man, that He should repent: has He said, and shall He not do it? or has He spoken, and shall He not make it good?"
The verse is not a statement about whether God can or will take on human nature. It is a statement about God's faithfulness and unchangeableness — that He does not share the moral weaknesses of men: lying, fickleness, and going back on His word. This is its clear meaning in context, where Balaam is being compelled by God to bless Israel against Balak's wishes.
C. H. Mackintosh explains Balaam's second parable:
C. H. MackintoshIn this very sublime parable, Israel's blessedness and security are made to depend, not on themselves, but upon the truth and faithfulness of Jehovah. "God is not a man that he should lie; neither the son of man that he should repent." This places Israel upon safe ground. God must be true to Himself. Is there any power that can possibly prevent Him from fulfilling His word and oath? Surely not. "He has blessed; and I cannot reverse it." God will not, and Satan can not reverse the blessing.
W. W. Fereday makes the same point:
W. W. FeredayThe opening words of his second discourse are exceedingly precious: "Rise up, Balak, and hear; hearken to me, thou son of Zippor: God is not a man, that He should lie; neither the son of man, that He should repent, has He not said, and shall He not do it? or has He spoken, and shall He not make it good?" ... Balaam's words in Num. 23:19 may well be read again and again. True, the words came from the lips of a bad man, but their source nevertheless was the Spirit of God.
J. N. Darby explains:
J. N. DarbyBalaam is obliged to bear witness to the character of God. "God is not a man that he should lie, neither the Son of man that he should repent," etc. He is not only a God of truth, but He does not alter it. He says, "Their sins and their iniquities will I remember no more." This speaks the unrepentingness of God. The truth that He tells is truth, eternal truth, and it is now in the mouth of the enemy. "I cannot reverse it." Not, I will not, but I cannot.
So Numbers 23:19 declares that God is not like man in His moral character — He does not lie, He does not change His mind, He does not fail to keep His word. It says nothing about whether the eternal Son of God could, in sovereign grace, take humanity into union with His divine Person.
The Incarnation: God Becoming Man Without Ceasing to Be God
The whole testimony of Scripture is that the eternal Word — who was God (John 1:1) — became flesh (John 1:14). This is not God turning into a man, nor ceasing to be God, but God taking on an additional nature in perfect manhood while remaining fully divine.
F. B. Hole makes a striking distinction:
F. B. HoleNo one can really confess Him "come in flesh," save those who believe in His Deity and His Manhood. He came in flesh, therefore He is Man. He — that Person — Jesus Christ, came in flesh. Therefore He is God. We mere men do not come in flesh. We are flesh.
This is a profound point. Ordinary human beings do not "come in" flesh — they simply are flesh. The very language of the incarnation presupposes a pre-existing divine Person who entered into a condition He was not in before.
J. N. Darby traces the same truth in John 1:
J. N. DarbyIn verse 14 we have what Christ became, not what He was, essentially ... He became a Man; and not only that, but He "dwelt among us" — not like God visiting Abraham merely. In outward form He was like another man — He was "found in fashion as a man." That is an immense truth; the Word comes and dwells among men as a Man, (more than a man, of course), "and we beheld his glory" ... "the glory as of an only begotten with a father."
F. B. Hole gives the fullest treatment in his essay "The Deity and Humanity of Christ," walking through six tremendous facts about "the Word" in John 1:1-4:
F. B. Hole1. "In the beginning was the Word." He did not begin to be in the beginning, but He was, i.e., He existed in the beginning. The Word has eternal existence. 2. "The Word was with God" ... The Word has distinct Personality. 3. "The Word was God." Though distinct as to His Person yet none the less God. The Word has essential Deity.
And:
Deity_HumanityThe truth as to the absolute and essential deity of the Lord Jesus is abundantly stated in Scripture, as also is the truth of the reality, fulness, and perfection of His Manhood. To start theorizing as to how these things can be is but the natural impertinence of the human mind. We rather take the place of believing what is revealed, bowing our heads and worshipping.
Two Natures in One Person
In the 1920 readings on the Person of Christ, C. Crain stated plainly:
C. CrainHe is both God and man; possessing divine sovereignty, and at the same time a submissive, subject man.
A. E. Booth added:
We need to press that. Humanity is never deified. Christ is perfect man and true God.
And Crain concluded:
CrainThere are two natures combined in one Person, yet distinct.
In his exposition of 1 John, Crain also wrote:
CrainThe incarnation is a profound mystery. The mind of man cannot explain it or understand how it was effected, but the fact is plainly evident. The power of the Holy Spirit in and through the virgin produced a Man who is both a divine and a human Person. Thus supernaturally come into the world, He unites Deity and humanity in Himself — in one Person. He is thus truly God and truly Man: with human spirit, soul and body — God is seen in flesh.
"The Son of Man" — A Title of Deity, Not a Denial of It
It is worth noting that when Christ calls Himself "the Son of Man", He is not diminishing His deity but asserting a unique glory. F. A. Hughes writes:
The title "the Son of Man" belongs uniquely to Christ. Both Ezekiel and Daniel are addressed as "son of man" without the definite article — they were that characteristically.
He connects this directly to Christ's assertion of deity:
SONOFMAN"When ye have lifted up the Son of Man, then shall ye know that I AM" (John 8:28). In this chapter we have from the lips of Christ what is perhaps the strongest assertion of His deity — "Before Abraham was, I AM" (v. 58).
J. Wilson Smith shows how both titles belong to the same Person:
J. Wilson SmithIn this question and answer, "whom say ye that I, the Son of man, am," and "Thou art the Christ, the Son of the living God," we have both facts stated as equally true — "the Son of man" and "the Son of God." Hence it becomes us to cherish both His perfect manhood and His essential deity.
Synthesis
Numbers 23:19 does not say "God can never become man." It says God is not like a man in His moral character — He does not lie, He does not change His mind, He does not go back on His promises. It is a statement about the unchangeableness and faithfulness of God, spoken in the context of Balaam being unable to reverse God's blessing on Israel.
The incarnation does not contradict this truth — it fulfils it. The eternal Son of God, who was God and was with God from the beginning, in sovereign grace became man without ceasing to be God. He did not exchange one nature for another; He took on a true and full human nature in addition to His eternal divine nature — two natures, distinct yet united in one Person, "perfect man and true God."
The distinction F. B. Hole draws is decisive: ordinary human beings do not "come in flesh" — they simply are flesh. But Christ came in flesh. That very language requires a divine Person who existed before the incarnation. He who was the Creator entered the ranks of creation, not by ceasing to be what He was, but by becoming what He had not been — truly man, while remaining truly God.