'Faithful Witness' in the Bible

A faithful witness does not lie, but he who breathes out falsehood is a witness of deceit.

Then they said to Jeremiah, "May Yahweh be against us as {a true and faithful witness} if we do not do according to all the words that Yahweh sends you for us.

and from Jesus Christ the faithful witness, the firstborn from the dead and the ruler of the kings of the earth. To the one who loves us and released us from our sins by his blood

'I know where you live, where the throne of Satan [is]. And you hold fast to my name and did not deny your faith in me, even in the days of Antipas my faithful witness, who was killed among you, where Satan lives.