Oh man... Happy nameday BTW.
Thank you, but I don't celebrate the feast of my saint, Peter the Aleut Martyr, until September 24.
(I guess I could claim yesterday as an indirect
nameday, since the Apostle Peter is ultimately the saint from whom all who bear the name Peter draw their name.
But I don't think that reasoning would fly very well with my priest.)
If I testify about myself, my testimony is not valid.source
I've never read this passage as indicating that Jesus didn't think Himself incapable of error. I've always understood that one needs to read this with an understanding of His audience. As I read His words here, Jesus is anticipating that those hearing Him speak will not believe His testimony about Himself--as Robert intimated above, only a fool boasts about himself. According to Jewish law (Deuteronomy 17:6), a valid testimony requires at least two witnesses, so Jesus offers as validation of His testimony the witness of others. Those Jesus offers as witnesses to corroborate His testimony about Himself are His Father, John the Forerunner, His own works, and the Jewish Scriptures. (See the next several verses that follow John 5:31.)