Why is it important for Christians to believe that Jesus is both God and man?

The understanding that Jesus is both fully God and fully man is foundational for Christian doctrine because our salvation hinges on this truth. Romans 5:12-19 illustrates that sin entered the world through one man, Adam, and thus must be dealt with by another man, Jesus Christ. If Jesus were merely a man, He could not bear the weight of sin for all of humanity. Conversely, if He were only God, He would lack the experiential understanding of human weakness and temptation. This unique duality allows Him to be the perfect mediator who satisfies God's justice while providing a relatable advocate for those He saves. As the God-man, Jesus embodies the qualities necessary to bridge the gap created by sin, making Him essential to the salvation of sinners.