I didn't know him, but for this reason I came baptizing in water: that he would be revealed to Israel."

 Again John explains a Hebrew word in order to help his Greek readers to understand better. Messiah and Christ are the same word. Messiah is Hebrew and Christ is Greek; both mean anointed. In the ancient world, as today in our own country, kings were anointed with oil at their coronation. Messiah and Christos both mean God's Anointed King. 