'Witness' in the Bible

It will be a sign and a witness to the LORD of the Heavenly Armies in the land of Egypt; when they cry out to the LORD because of their oppressors, he will send them a savior, and he will come down and rescue them.

"Go now, and write it down on a tablet in their presence, inscribing it in a book, so that for times to come it may be an everlasting witness.

"Look! I have made him a witness to the nations, a leader and commander of the nations.