Whoever speaks on his own is after his own glory; but whoever seeks the glory of the one who sent him — that man is truthful, and there is no wrong in him.
In context
16Jesus answered them, “My teaching is not my own; it belongs to the one who sent me. 17If anyone wants to do his will, he will find out about this teaching — whether it comes from God, or whether I speak on my own. 18Whoever speaks on his own is after his own glory; but whoever seeks the glory of the one who sent him — that man is truthful, and there is no wrong in him. 19Did Moses not give you the law? Yet none of you keeps the law. Why are you trying to kill me?” 20The crowd answered, “You have a demon! Who is trying to kill you?”