Jesus is both God and man because He is the God-man, fully divine and fully human, as reflected in the hypostatic union.
The doctrine of the hypostatic union asserts that Jesus Christ is both fully God and fully man in one person. This union is essential for understanding His role in redemption. As the eternal Son of God, He possesses a divine nature, while His incarnation through the Virgin Mary allows Him to take on a complete human nature. Colossians 2:9 states, 'For in Him dwells all the fullness of the Godhead bodily,' emphasizing that Jesus is not a mere representative of God but God Himself in human form. His dual nature is necessary because only as a human could He represent humanity and bear our sins, and only as God could His sacrifice possess the infinite value necessary to atone for the sins of many.
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