Why then baptizest thou? (Ti oun baptizei;). In view of his repeated denials (three here mentioned). If thou art not (ei su ouk ei). Condition of first class. They did not interpret his claim to be "the voice" to be important enough to justify the ordinance of baptism. Abrahams (Studies in Pharisaism and the Gospels) shows that proselyte baptism was probably practised before John's time, but its use by John was treating the Jews as if they were themselves Gentiles.