R. Moshe Feinstein on What Constitutes Marit Ayin (22 Shevat)

אגרות משה אבן העזר א:לה 22 Shevat 5694 (1934)

What's the nature of mar'it ayin, of the prohibition to act in ways that will lead others to see us as doing something wrong? Based on the prohibition to marry one's father-in-law's former wife (who is not the mother of one's wife), R. Moshe Feinstein articulates a narrower version of mar'it ayin than we might expect.