What is my duty towards someone who commits abominations (precursors to sodomy) in my class, and someone who plays music on the bus, knowing that my mother advised me to politely ask them to lower the volume? And is it obligatory for me to forbid evil (al-nahy ‘an al-munkar)? And what should I do with someone who slanders me in class? And what is the ruling on completing my prayer in the row behind me if I miss a rak'ah with the imam?

The scholars have agreed upon the necessity of enjoining good and forbidding evil (al-amr bil-ma'ruf wal-nahy anil-munkar) and working to change evil to the best of one's ability. It is a communal obligation (fard kifayah) and may become an individual obligation (fard 'ayn). Whoever sees an evil should change it with his hand; if he cannot, then with his tongue; if he cannot, then with his heart, and that is the weakest of faith. Homosexuality (liwāṭ) is one of the gravest major sins, and Islam has prescribed severe punishment for it. Music accompanied by instruments is unanimously forbidden. There is no sin upon one who does not intend to listen, but it is obligatory to avoid sitting with those who are committing sins at the time they are doing so. Whoever sits with them should call them to the truth, and if they do not respond, he must isolate himself from them.