Translation:

52. Say: "Enough is Allah for a Witness between me and you: He knows what is in the heavens and on earth. And it is those who believe in vanities and reject Allah that will perish (in the end)."

Notes (Tafseer)

3483. The test of a Revelation is whether it comes from Allah or not. This is made clear by the life and teachings of the Messenger who brings it. No fraud or falsehood can for a moment stand before Allah. All the most hidden things in heaven and earth are open before Him.

3484. If Truth is rejected, Truth does not suffer. It is the rejecters who suffer and perish in the end.