'Witness' in the Bible

(For the life was manifested, and we have seen it, and bear witness, and shew unto you that eternal life, which was with the Father, and was manifested unto us;)

This is he that came by water and blood, even Jesus Christ; not by water only, but by water and blood. And it is the Spirit that beareth witness, because the Spirit is truth.

And there are three that bear witness in earth, the spirit, and the water, and the blood: and these three agree in one.

If we receive the witness of men, the witness of God is greater: for this is the witness of God which he hath testified of his Son.

He that believeth on the Son of God hath the witness in himself: he that believeth not God hath made him a liar; because he believeth not the record that God gave of his Son.