[an act of worship?! And if it has not been established that anything among [acts of worship] is forbidden, how can it be ruled] prohibited? Accordingly, Ahmad and other jurists of the hadith tradition used to say: The basic rule governing acts of worship is that they are confined to revealed prescription; none may be prescribed except what Allah has prescribed. Otherwise, we would fall within the meaning of His saying, Most High: “Or do they have partners who have prescribed for them a religion which Allah has not authorized?” [al-Shūrā: 21] [al-Shūrā: 21].

The basic rule governing customary practices, however, is permissibility; none may be prohibited except what He has forbidden. Otherwise, we would fall within the meaning of His saying: “Say, ‘Have you considered the provision Allah has sent down for you, some of which you have made unlawful and some lawful?’” [Yūnus: 59] [Yūnus: 59]. This is why Allah condemned the polytheists who prescribed in religion what Allah had not authorized and prohibited what He had not prohibited. In Sūrat al-Anām, He says:

“They assigned to Allah a share of the crops and livestock He created, saying, ‘This is for Allah’—so they claim—‘and this is for our partners.’ Yet what was for their partners did not reach Allah, while what was for Allah did reach their partners. Evil indeed was their judgment. — Likewise, their partners made the killing of their children appealing to many of the polytheists, in order to destroy them and confuse their religion for them. Had Allah willed, they would not have done so. Therefore, leave them to their fabrications. — They also said, ‘These livestock and crops are forbidden; none may eat of them except whom we will’—so they claim. Some livestock were forbidden to be ridden, and over others they did not mention Allah’s name, fabricating lies against Him. He will repay them for what they used to fabricate.” [al-Anām: 136–138] [al-Anām].

Thus, He mentioned what they had innovated in acts of worship and prohibitions.

In Sahīh Muslim, Iyād ibn Himār (may Allah be pleased with him) reported that the Prophet (peace and blessings be upon him) said: “Allah Most High said: ‘I created My servants upright, but the devils led them astray. They forbade them what I had made lawful for them and commanded them to associate with Me things for which I had sent down no