'Faithful Witness' in the Bible

It will be established forever like the moon, a faithful witness in the sky." Interlude

Then they told Jeremiah, "May the LORD be a true and faithful witness against us if we don't do everything that the LORD your God tells us through you.

"I know where you live. Satan's throne is there. Yet you hold on to my name and have not denied your faith in me, even in the days of Antipas, my faithful witness, who was killed in your presence, where Satan lives.