Al-An'aam 6:159

Those who have made divisions in their religion and turned into factions[56], you have nothing to do with them. Their case rests with Allah alone; He will inform them of what they used to do.

[56] The People of the Book or others.

Indeed, those who have divided their religion and become sects - you, [O Muḥammad], are not [associated] with them in anything. Their affair is only [left] to Allāh; then He will inform them about what they used to do.

159. Verily, those who divide their religion and break up into sects (all kinds of religious sects)[21], you (O Muhammad صلى الله عليه وسلم) have no concern in them in the least. Their affair is only with Allâh, Who then will tell them what they used to do.

[21] (V.6:159) It is said that the Prophet صلى الله عليه وسلم recited this Verse and said: "These people are those who invent new things (Bid‘ah) in religion and the followers of the vain desires of this Muslim nation, and their repentance will not be accepted by Allâh." (TafsirAl-Qurtubi).
[It has been narrated in the Hadîth Books (At-Tirmidhi, Ibn Mâjah and Abu Dâwûd) that the Prophet صلى الله عليه وسلم said: "The Jews and the Christians will be divided into seventy-one or seventy-two religious sects and this nation will be divided into seventy-three religious sects, - all in Hell, except one, and that one is: on which I and my Companions are today, i.e. following the Qur’ân and the Prophet’s Sunnah (legal ways, orders, acts of worship, statements)"].

Lo! As for those who sunder their religion and become schismatics, no concern at all hast thou with them. Their case will go to Allah, Who then will tell them what they used to do.