Jesus Christ is often misunderstood. The phrase 'fully man and fully God' does not have biblical support; Christ's real nature is much more meaningful.
The Bible records that Jesus of Nazareth's Father was God and His mother was Mary, a human. What, then, was His nature? Was He a man? Was He divine?
Baptism and being born again were already understood by the Jews, but the traditions had evidently blinded people to some additional spiritual nuances.