“But no, by your Lord! They will not truly believe until they make you judge in all disputes between them, then find no discomfort in their hearts over your judgment, but accept it wholeheartedly.” [al-Nisāʾ: 65]

And the Exalted says:

“It is not for a believing man or woman, when Allah and His Messenger have decided a matter, to have any choice in their affair. Whoever disobeys Allah and His Messenger has clearly gone astray.” [al-Aḥzāb: 36]

And the Exalted says:

“Let those who oppose his command beware, lest a trial befall them or a painful punishment overtake them.” [al-Nūr: 63]

Al-ʿIrbāḍ ibn Sāriyah narrated: “The Messenger of Allah ﷺ delivered to us an exhortation that brought tears to our eyes and filled our hearts with fear. We said, ‘O Messenger of Allah, it is as though this is a farewell exhortation. So what do you enjoin upon us?’ He said, ‘I have left you upon the clear way, whose night is like its day. None deviates from it after me except one who is ruined. Whoever among you lives on will see much disagreement. So adhere to what you know of my sunnah and the sunnah of the rightly guided caliphs. Hold fast to it with your molar teeth, and beware of newly introduced matters, for every newly introduced matter is misguidance.’”

ʿAbd Allah ibn Masʿūd narrated: “The Messenger of Allah ﷺ drew a line for us, then drew lines to its right and left. He then said, ‘These are paths; upon every one of them is a devil calling to it.’ Then he recited:

‘And indeed, this is My straight path, so follow it, and do not follow the other ways, lest they lead you away from His way.’ [al-Anʿām: 153]”

Ibn Masʿūd said: “Follow, and do not innovate, for you have been sufficiently provided for.”