John 3:16
For God so loved the world that He gave His only begotten Son, that everyone who believes into Him would not perish, but would have eternal life.
We need to believe that Jesus is the Son of God because His Person as the Son of God is a matter of eternal life. But in order for the Son of God to carry out His commission to impart Himself into us as life, He must be God’s anointed One. It is by being the Christ that the Lord Jesus imparts Himself into us as the Son of God so that we may have eternal life.