Is the prohibition by the Prophet, peace be upon him, "Do not associate except with a believer," to be understood as an outright prohibition (tahrim) or as a disapproval (karahah), especially if the association is with a Muslim who is a transgressor (fasiq) but loves Allah and His Messenger, and does not involve participation in or approval of unlawful acts? And what is meant by "believer" in this hadith?

The Sharia has warned against associating with evil people and forbidden mixing with the impious. The Prophet, peace and blessings be upon him, said: "The example of a good companion and a bad companion is like that of the perfume seller and the blacksmith. The perfume seller will either give you some perfume, or you will buy some from him, or you will find a good scent from him. And as for the blacksmith, he will either burn your clothes, or you will smell a bad odor from him." And "A man is upon the religion of his intimate friend, so let one of you look at whom he befriends." And "Do not accompany anyone but a believer, and let no one eat your food except a pious person."

Associating with the righteous leads to success and prosperity, and observing people of piety influences one towards righteousness.

An exception to this prohibition is accompanying a disbeliever or an evildoer for the purpose of giving advice and inviting them to good, provided there is security from harm and being influenced by them.