“The believers, men and women, are allies of one another; they enjoin what is right and forbid what is wrong.” [al-Tawbah: 71]
And His words, Exalted is He:
“Those who, if We establish them in the land, establish prayer, give zakah, enjoin what is right, and forbid what is wrong.” [al-Hajj: 41]
And the words of the Messenger of Allah, blessings and peace be upon him:
“By Him in Whose hand is Muhammad’s soul, you must enjoin what is right, forbid what is wrong, restrain the foolish, and firmly compel them to follow the truth. Otherwise, Allah will surely turn your hearts against one another and curse you as He cursed the Children of Israel. When a sensible person among them committed a sin, someone would rebuke them for it. Yet the next day he would sit with the offender, eat with him, and drink with him, as though he had not seen him committing a sin the day before. When Allah saw this from them, He turned their hearts against one another and cursed them through the words of their prophets David and Jesus, son of Mary, peace be upon them both: ‘That was because they disobeyed and used to transgress.’ [al-Baqarah: 61]”
When wrongs become widespread in the streets—such as wine being carried through them, men walking with young women and conversing with them, and similar overt wrongs—the ruler must put an end to them to the best of his ability by appointing someone charged with monitoring and addressing them. The Messenger of Allah, blessings and peace be upon him, said:
“Allah does not punish the general public for the deeds of particular individuals. But when wrongdoing is committed openly, they all become deserving of punishment.”
It is recommended for someone whom the ruler calls upon to undertake this task to accept, if he knows that he has the strength to carry it out, because this involves cooperating in doing good. Allah, Mighty and Majestic, says:
“Cooperate with one another in righteousness and piety, but do not cooperate in sin and aggression.” [al-Mā’idah: 2]
Anyone who witnesses any such wrongdoing or encounters it on his way must oppose it, subject to the three conditions already mentioned. If he cannot do so with his hand or his tongue, he must reject it in his heart.
As for the words of Allah, Mighty and Majestic:
“O you who believe, take care of yourselves. Those who go astray cannot harm you if you are rightly guided.” [al-Mā’idah: 105]