John 5:31

If I bear witness of myself (Ean egw marturw peri emautou). Condition of third class, undetermined with prospect of determination (ean and present active subjunctive of marturew). The emphasis is on egw (I alone with no other witness). Is not true (ouk estin alhqh). In law the testimony of a witness is not received in his own case (Jewish, Greek, Roman law). See Deuteronomy 19:15 and the allusion to it by Jesus in Matthew 18:16 . See also 2 Corinthians 13:1 ; 1 Timothy 5:19 . And yet in 8:12-19 Jesus claims that his witness concerning himself is true because the Father gives confirmation of his message. The Father and the Son are the two witnesses ( 8:17 ). It is a paradox and yet true. But here Jesus yields to the rabbinical demand for proof outside of himself. He has the witness of another (the Father, Jo 5:32 Jo 5:37 ), the witness of the Baptist ( 5:33 ), the witness of the works of Jesus ( 5:36 ), the witness of the Scriptures ( 5:39 ), the witness of Moses in particular ( 5:45 ).