John 1:31

And I knew him not (kagw ouk hdein auton). Repeated in verse 1 John 33 . Second past perfect of oida as imperfect. He had predicted the Messiah and described him before he met him and baptized him. See the Synoptics for that story. Whether John knew Jesus personally before the baptism we do not know. But that he should be made manifest to Israel (all ina panerwqh twi Israhl). Final clause with ina and first aorist passive subjunctive of panerow. The purpose of John's ministry was to manifest to Israel with their spiritual privileges ( 1 John 1:49 ) the presence of the Messiah. Hence he was baptizing in water those who confessed their sins, he means, as in Mark 1:5 . The Synoptic account is presupposed all along here.