Do Christians even know that?

As I understand it, the messianic title was "Son of Man," which is what Jesus is called in most of the Gospels. John is the one who keeps referring to his as "Son of God," and John is also the one who stresses Jesus' divinity, with his introduction ("In the beginning there was the Word, and the Word was with God, and the Word was God") and putting words in Jesus' mouth where Jesus claims to be one with God ("Verily, verily I say unto you, before even Abraham was, I Am").