If I alone bear witness about myself, my testimony is not true.
31. If I testify concerning myself. He does not here take any thing away from the credit due to his testimony, which he elsewhere asserts in strong terms, but he speaks by way of concession; for Christ, having been in other respects most abundantly supported, consents that they should not believe his word.
In these verses our Lord Jesus proves and confirms the commission he had produced, and makes it out that he was sent of God to be the Messiah. I. He sets aside his own testimony of himself (Joh 5:31): "If I bear witness of myself, though it is infallibly true (Joh 8:14), yet, according to the common rule of judgment among men, you will not...
Commenting on John 5:31-47
If I bear witness of myself,.... Which was not allowed any man to do; nor indeed is it proper that a man should be a witness in his own cause: and, according to the Jewish canons, a man might not be a witness for his wife, because she was reckoned as himself.