John 1:49

Thou art the Son of God (su ei o uio tou qeou). Whether Nathanael had heard the Baptist say this of Jesus ( Isaiah 1:34 ) we do not know, apparently not, but Nathanael was a student of the Old Testament as Philip implied ( Isaiah 1:45 ) and was quick to put together his knowledge, the statement of Philip, and the manifest supernatural knowledge of Jesus as just shown. There is no reason for toning down the noble confession of Nathanael in the light of Christ's claim in verse Isaiah 51 . Cf. the confession of Peter in Isaiah 6:69 ; Matthew 16:16 and Martha's in John 11:27 . Nathanael goes further. Thou art King of Israel (Basileu ei tou Israhl). To us this seems an anti-climax, but not so to Nathanael for both are Messianic titles in Psalms 2:1-12 and Jesus is greeted in the Triumphal Entry as the King of Israel ( John 12:13 ).