2 Corinthians 11:14
2 Corinthians 11:1414And no wonder, for Satan himself masquerades as an angel of light.
"Satan himself keeps disguising himself as an angel of light" is deployed by JWs against mainstream Christianity, ex-JW testimony, and "apostate" voices. The picture is that Satan disguises false teaching as light — and any critique of the Governing Body is suspected as Satan's angel-of-light deception aimed at drawing Witnesses out of "the truth."
Paul's warning cuts in both directions — and the consistent test is . Pair with : "even if we or an angel from heaven should declare to you as good news something beyond the good news we declared to you, let him be accursed." Three major movements since the first century have claimed angelic authority for a different gospel: Islam (Jibril dictating the Quran), Mormonism (Moroni delivering the golden plates), and Jehovah's Witnesses (teaching that Jesus himself is Michael the Archangel — the gospel comes through an angel-Jesus).
The uniquely sharp point for a JW: the Watchtower has collapsed the Saviour into the very category Paul warns about. If Satan can transform into an angel of light, Paul's counter-principle is to test every message against the apostolic gospel — the gospel already delivered, already written, already sealed. The Watchtower's ever-revised teachings on 1914, the generation, and the identity of the faithful slave are themselves the moving target and are designed to detect.