الأمر بالمعروف والنهي عن المنكر
al-Amr bi-l-Maʿrūf wa-l-Nahy ʿan al-Munkar
Topic
Commanding what is commonly known as good and forbidding what is evil or undesirable, a duty laid on the Muslim community.
What it means
Maʿrūf is what is known and recognised as good, and munkar is what is rejected as evil or undesirable. The Quran says, “Let there be among you a community who call to good, enjoin what is right and forbid what is wrong” (3:104), and it describes the believers as “the best community brought forth for people” because they do so (3:110). The duty belongs to the whole community, and scholars attach conditions to it: knowledge of the matter, gentleness in manner, and care that the correction does not cause a greater harm.
Often misunderstood as
It is often equated with a religious police, whereas in the Quran it is a duty of the whole community carried out with knowledge and gentleness.
What the sources say
A hadith in Sahih Muslim, reported by Abu Said al-Khudri, says that whoever sees a wrong should change it by hand, and if unable then by tongue, and if unable then by heart, which is the weakest degree of faith.
Term and Arabic as listed in Ismail al Faruqi, Toward Islamic English (International Institute of Islamic Thought, 1995), p. 63, listed as AL AMR BIL MA‘RŪF WAL NAHY ‘AN AL MUNKAR. The definition is restated here.