'Witness' in the Bible

The shew of their countenance doth witness against them; and they declare their sin as Sodom, they hide it not. Woe unto their soul! for they have rewarded evil unto themselves.

And it shall be for a sign and for a witness unto the LORD of hosts in the land of Egypt: for they shall cry unto the LORD because of the oppressors, and he shall send them a saviour, and a great one, and he shall deliver them.

Behold, I have given him for a witness to the people, a leader and commander to the people.