53-1 (The author of the book narrated) my father - may God be pleased with him - narrated that Sa’d ibn Abdullah quoted on the authority of Abdullah ibn Aamir ibn Sa’d, on the authority of Abdul Rahman ibn Abi Najran, “Abul Hassan Ar-Ridha’ (a.s.) wrote a letter to some of his companions which he read to me. It said, ‘
We know (all about) men when we see them. We recognize their true faithfulness or hypocrisy.’”