The apostle John expresses a fundamental truth of Christianity when he writes, “the Word became flesh” (John 1:14). This profound statement reveals the great mystery that the Second Person of the Trinity—God the Son—became human without losing His divine nature. But why was His incarnation necessary?
Because it was destined before the foundation of the world
The plan of redemption, that Jesus came to rescue his people from their sins (Matthew 1:21), was established from before the foundation of the world (Ephesians 1:3-10). Therefore, his incarnation was determined in eternity and was manifested in time (1 Peter 1:20). We see this redemptive plan from the garden of Eden (Genesis 3:15) passing through the law, the prophets, and the Psalms until it reaches its fulfillment in Jesus (Luke 24:44; Galatians 3:16; 4:4).
Because He is the human representative of all the redeemed
Adam was the representative of all humanity and we were all considered sinners when he disobeyed God’s command; however, this “first Adam” did not have an end in itself, but pointed to the “last Adam” (1 Corinthians 15:45-47), that is to say, Jesus, as the human representative of all redeemed humanity (Ephesians 1:22-23; Colossians 1:24). Jesus fulfilled His assigned work at every point where the “first Adam” failed, to redeem His people from their sins (Romans 5:18-21).
Because man had to rule and subdue the earth
In Genesis 1–2, Moses reveals that God created humanity in His image and gave them the responsibility to rule and subdue the earth (Genesis 1:26–28). Adam failed to fulfill this mandate. However, Jesus, the “last Adam,” became incarnate and, by His obedience to the Father, secured the right to rule and subdue all of creation, as the firstborn of all creation (Hebrews 2:7–9). In Him, God’s original purpose for humanity is fulfilled.
Because He is the mediator of the New Covenant
In the Old Covenant, God used prophets (Deuteronomy 18:18–22; Isaiah 1:2–20), priests (Exodus 28:30; Leviticus 8:8), and kings (1 Chronicles 21) to mediate between Himself and His people. However, Jesus is the perfect and only mediator between God and humanity (1 Timothy 2:5). He fulfills the roles of the greatest prophet, the perfect high priest, and the eternal King, acting as the mediator of the New Covenant (Hebrews 8:6; 9:15; 12:24; 1 Corinthians 1:30). Through His death, He guarantees a better covenant (Hebrews 7:22; 7:27).
Because He is the standard of true humanity
To fully understand what it means to be human, we must look to the person of Jesus. Though He was tempted in every way, He knew no sin (2 Corinthians 5:21; John 8:46). In Him is the perfect reflection of God’s image—not the distorted image of humanity that bears God’s image but is corrupted by sin. For Christians, Jesus is the highest example of holiness (1 Peter 2:21) and the hope that we will one day be fully conformed to His image (1 Corinthians 15:49).
Because He wanted to live among us
From eternity, God determined to live with His people forever. This was first seen in the Garden of Eden, where God walked with Adam and Eve. But when they sinned, they were cast out of His presence. Before sending them away, however, God promised to restore communion with His people through the seed of the woman (Genesis 3:15). This promise was progressively fulfilled through the ark, the tabernacle, and the temple, but its ultimate fulfillment came in the incarnation of Jesus, who “dwelt among us” (John 1:14) and is the perfect image of the Father (John 1:18).