In the beginning was the Word, and the Word was with God, and the Word was God…And the Word became flesh, and dwelt among us, and we saw His glory, glory as of the only begotten from the Father, full of grace and truth. (John 1:1, 14)
John uses simple words to reveal profound truth…“And the Word became flesh, and dwelt among us” (John 1:14a). At a point in time, God the Son added to Himself humanity, forever uniting His divine nature with a perfect sinless human nature, becoming the God-man. In the field of systematic theology, this is called the hypostatic union. “Though His deity is eternal, the humanity was gained in time. Therefore, the theanthropic Person—destined to be such forever—began with the incarnation.” God the Son did not indwell a human, but forever added humanity to Himself. “When Christ came, a Person came, not just a nature; He took on an additional nature, a human nature—He did not simply dwell in a human person. The result of the union of the two natures is the theanthropic Person (the God-man).” Reading through the Gospels, there were times that Jesus operated from His divine nature (Mark 2:5-12; John 8:56-58; 10:30-33), and other times from His human nature (Matt. 4:2; Luke 8:22-23; John 19:28). Concerning both natures, Paul Enns writes:
The two natures of Christ are inseparably united without mixture or loss of separate identity. He remains forever the God-man, fully God and fully man, two distinct natures in one Person forever. Though Christ sometimes operated in the sphere of His humanity and in other cases in the sphere of His deity, in all cases what He did and what He was could be attributed to His one Person. Even though it is evident that there were two natures in Christ, He is never considered a dual personality. In summarizing the hypostatic union, three facts are noted: (1) Christ has two distinct natures: humanity and deity; (2) there is no mixture or intermingling of the two natures; (3) although He has two natures, Christ is one Person.
Jesus is the God-Man. He is eternal God (Isa. 9:6; John 8:56-58), yet He was born of a woman in time and space (Gal. 4:4). He is omniscient (Ps. 139:1-6), but as a boy, He grew in knowledge (Luke 2:52). He created the universe (Gen. 1:1; John 1:3; Col. 1:15-16), but as man, He is subject to its weaknesses (Matt. 4:2; John 19:28). Concerning the complexity of the union, Lewis S. Chafer states:
The reality in which undiminished Deity and unfallen humanity united in one Theanthropic Person has no parallel in the universe. It need not be a matter of surprise if from the contemplation of such a Being problems arise which human competency cannot solve; nor should it be a matter of wonder that, since the Bible presents no systematized Christology but rather offers a simple narrative with its attending issues, that the momentous challenge to human thought and investigation which the Christ is, has been the major issue in theological controversy from the beginning to the present time.
We struggle to comprehend the union of God and Man; however, it is with certainty that the Bible portrays Him this way (John 1:1, 14; 20:28; cf. Luke 1:31-33; 2 Cor. 5:21; Heb. 4:15), and this truth is essential to Christianity. As God, Jesus is worthy of all worship and praise (Luke 24:51-52; John 9:38; 20:28; Heb. 1:6). As a perfect sinless Man, He went to the cross and died a substitutionary death in my place (Mark 10:45; Rom. 5:6-10; 1 Cor. 15:3-4; 1 Pet. 3:18), and bore the wrath of God that rightfully belonged to me (Isa. 53:1-12), so that I might have the gifts of righteousness and eternal life (John 3:16; 10:28; 2 Cor. 5:21; Phil. 3:9). What a blessing my Savior is to me.
Dr. Steven R. Cook
 Lewis S. Chafer, Systematic Theology, Vol. 1 (Grand Rapids, Michigan: Kregel Publications, 1993), 383.
 Paul P. Enns, Moody Handbook of Theology, (Chicago, Illinois: Moody Press, 1989), 227.
 Paul P. Enns, Moody Handbook of Theology, 225.
 Lewis S. Chafer, Systematic Theology, Vol. 1, 387.