When people talk about Jesus they often do not correlate the fact that He was not just a man. The fact that He referred to Himself as the Son of God also lends itself to the confusion. Jesus must have had a beginning, many people deduce this from the term son. Truly, if Jesus had a beginning and was a son, then He would have been made subordinate to the Father, right? It was and is asserted by many that Jesus is not equal to the Father, who is eternal, but had a beginning point.
This view above is called Arianism and it is not considered orthodox Christianity. Jesus was fully God and fully man in one person. He was two “whats” in one “who.” Now, why would this be so important to the faith? It is important because only God could save us and only humanity needed the saving. He bore our sins and acted as the sacrifice, providing an atonement for our transgressions. Jesus acted as the bridge between God and humanity. He became the perfect High Priest as the Book of Hebrews discussed about at great lengths. I would recommend that you read that book carefully and see what the author argued for in their work. Jesus was described as “the radiance of the glory of God and the exact imprint of his nature, and he upholds the universe by the word of his power” (Heb 1:3). Jesus is the great High Priest who intercedes for us before the throne of God, able to save and redeem His people, those people who are eagerly waiting for Him (Heb 9:28).
As a side note– God is not a Christian. A Christian is a Christ follower, a little Christ. God revealed Himself to us through the Bible and definitively in the person of Jesus the Messiah. Those who follow Christ are to be considered Christians (and certainly God does not do that…). Jesus referred to Himself in the Gospel according to John that He was “I AM.” He directly equated Himself to the God of Abraham, Isaac and Jacob. We have to take Jesus at His own word here, for this is a very bold statement. To echo CS Lewis, he was either a liar, lunatic or the very person He claimed to be– God. Quite frankly I see no other option.