'Witness' in the Bible

because they have committed an outrage in Israel by committing adultery with their neighbors’ wives and have spoken a lie in My name, which I did not command them. I am He who knows, and I am a witness.” This is the Lord’s declaration.

And they said to Jeremiah, “As for every word the Lord your God sends you to tell us, if we don’t act accordingly, may the Lord be a true and faithful witness against us.