Isaiah 9:6 For unto us a child is born, unto us a son is given: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counselor, The Mighty God, The everlasting Father, The Prince of Peace.
Even though Jesus was the "Son of Man", He was also the "Son of God". He was more than just a man, He was the God-man. Believing that is essential to being saved.
John 20:31 But these are written that ye might believe that Jesus is the Christ, the Son of God: and that believing, ye might have life through his name.
"A Son is given" reminds us that this God-man came into the world to deliver Himself up as the ransom for sin on the cross of Calvary.
No wonder they call Him Wonderful.