'Testimony is True' in the Bible

Jesus answered them, "Even if I do testify to myself, my testimony is true, because I know where I have come from and where I am going. But you do not know where I come from or where I am going.

The man who saw it has testified to it -- and his testimony is true, and he knows that he is telling the truth -- in order that you too may come to believe it.

This is the disciple who testifies to these things and who wrote them down, and we know that his testimony is true.