Translation:

73. "And believe no one unless he follows your religion." Say: "True guidance is the guidance of Allah; (fear ye) lest a revelation be sent to someone (else) like unto that which was sent unto you. Or that those (receiving such revelation) should engage you in argument before your Lord." Say: "All bounties are in the hand of Allah: He granteth them to whom He pleaseth; and Allah careth for all and He knoweth all things."

Notes (Tafseer)

407. The two clauses following have been variously construed, and some translations leave the sense ambiguous. I have construed the conjunction "an" to mean "lest", as it undoubtedly does in vii. 172. 'an taqulu", etc.

408. Cf. ii. 76. The People of the Book were doubly annoyed at the Muslims: (1) that they should (being outside their ranks) receive Allah's revelations, and (2) that having received such revelations, they should be able to convict them out of their own scriptures before their Lord.