The Prophet ﷺ said, "To proceed, the best of speech is the Book of Allah, the best of guidance is the guidance of Muhammad, the worst of affairs are the newly invented ones, every newly invented matter is an innovation, and every innovation is misguidance."Wazad in another narration, "And every misguidance is in the Fire."
عن النبي ﷺ قال: أما بعد، فإن خير الحديث كتاب الله، وخير الهدي هدي محمد، وشر الأمور محدثاتها، وكل محدثة بدعة وكل بدعة ضلالة. وزاد في رواية: وكل ضلالة في النار.
Muslim narrated it in the Book of Friday Prayer (43:867) from Muhammad bin Muthanna, Abdul-Wahhab bin Abdul-Majid told us, from Jafar bin Muhammad, from his father, from Jabir bin Abdullah, and he related it in the description of the sermon of the Prophet ﷺ. Tirmidhi also narrated it (1578), and Ibn Khuzayma graded it sahih (1785), both of them from Utba bin Abd, Ibn Mubarak informed us, from Sufyan, from Jafar bin Muhammad, from his father, from Jabir bin Abdullah, who related something similar, adding, "And every deviation is in the Fire." Its chain is hasan because of Utba bin Abd, who is al-Yahmadi, for he is hasan al-hadith.As for what has been reported from Ibn Abbas as a raised report, "Allah refuses to accept the deed of an innovator until he abandons his innovation," its chain is a continuous chain of unknown narrators. Ibn Majah narrated it (50) from Abdullah bin Saeed, Bishr bin Mansur al-Hannat told us, from Abu Zaid, from Abu Mughira, from Abdullah bin Abbas, who related it. Its chain is daif. Abu Zura Razi said, "I do not know Abu Zaid, nor Abu Mughira, nor Bishr bin Mansur who reported from this Abu Zaid." (Jarh wa Tadil 9/373).Many reports have come down from the companions warning against innovation in religion. Among them is what has been established from Ibn Masud, who said, "Indeed the best speech is the Book of Allah, and the best guidance is the guidance of Muhammad ﷺ, and the worst of matters are those newly invented," "What you are promised is certainly coming, and you cannot prevent it" [Anam 6:134]. Bukhari narrated it in the Book of Holding Fast (7277) from Adam bin Abu Iyas, Shuba told us, Amr bin Mura informed us, I heard Mura Hamdani say, Abdullah said, and he related it.Among them also is what has been established from Huzaifa, who said, "O company of reciters, keep straight, for you have gone far ahead, but if you turn to the right or to the left, you will have strayed far into error." Bukhari narrated it in the Book of Holding Fast (7282) from Abu Naeem, Sufyan told us, from Amash, from Ibrahim, from Hammam, from Huzaifa, and he related it.