'Bear Witness' in the Bible

So the dragon was enraged with the woman, and he went off to wage war on the rest of her children (seed), those who keep and obey the commandments of God and have the testimony of Jesus [holding firmly to it and bearing witness to Him].

I, Jesus, have sent my messenger, to bear witness unto you of these things, for the assemblies. I, am the Root and the Offspring of David, the bright and the morning Star.

I, bear witness, unto every one that heareth the words of the prophecy of this scroll: - If anyone shall lay aught upon them, God, will lay upon him, the plagues which are written in this scroll;