6:159
إِنَّ ٱلَّذِينَ فَرَّقُوا۟ دِينَهُمْ وَكَانُوا۟ شِيَعًۭا لَّسْتَ مِنْهُمْ فِى شَىْءٍ ۚ إِنَّمَآ أَمْرُهُمْ إِلَى ٱللَّهِ ثُمَّ يُنَبِّئُهُم بِمَا كَانُوا۟ يَفْعَلُونَ
Indeed, those who have divided their religion and become sects - you, [O Muhammad], are not [associated] with them in anything. Their affair is only [left] to Allah; then He will inform them about what they used to do.
Translation · Saheeh International
Tafsir
Ibn Kathīr (abridged)
Criticizing Division in the Religion
Mujahid, Qatadah, Ad-Dahhak and As-Suddi said that this Ayah was revealed about the Jews and Christians. Al-`Awfi said that Ibn `Abbas commented,
إِنَّ الَّذِينَ فَرَّقُواْ دِينَهُمْ وَكَانُواْ شِيَعًا
(Verily, those who divide their religion and break up into sects...) "Before Muhammad was sent, the Jews and Christians disputed and divided into sects. When Muhammad was sent, Allah revealed to him,
إِنَّ الَّذِينَ فَرَّقُواْ دِينَهُمْ وَكَانُواْ شِيَعًا لَّسْتَ مِنْهُمْ فِى شَىْءٍ
(Verily, those who divide their religion and break up into sects, you have no concern with them in the least.) It is apparent that this Ayah refers to all those who defy the religion of Allah, or revert from it. Allah sent His Messenger with guidance and the religion of truth so that He makes it victorious and dominant above all religions. His Law is one and does not contain any contradiction or incongruity. Therefore, those who dispute in the religion,