religious sectarianism

وَقَالَتِ ٱلْيَهُودُ لَيْسَتِ ٱلنَّصَـٰرَىٰ عَلَىٰ شَىْءٍ وَقَالَتِ ٱلنَّصَـٰرَىٰ لَيْسَتِ ٱلْيَهُودُ عَلَىٰ شَىْءٍ وَهُمْ يَتْلُونَ ٱلْكِتَـٰبَ ۗ كَذَٰلِكَ قَالَ ٱلَّذِينَ لَا يَعْلَمُونَ مِثْلَ قَوْلِهِمْ ۚ فَٱللَّهُ يَحْكُمُ بَيْنَهُمْ يَوْمَ ٱلْقِيَـٰمَةِ فِيمَا كَانُوا۟ فِيهِ يَخْتَلِفُونَ

The Jews say, "The Christians have nothing [true] to stand on," and the Christians say, "The Jews have nothing to stand on," although they [both] recite the Scripture. Thus do those who know not [i.e., the polytheists] speak the same as their words. But Allāh will judge between them on the Day of Resurrection concerning that over which they used to differ.

وَمَا تَفَرَّقُوٓا۟ إِلَّا مِنۢ بَعْدِ مَا جَآءَهُمُ ٱلْعِلْمُ بَغْيًۢا بَيْنَهُمْ ۚ وَلَوْلَا كَلِمَةٌ سَبَقَتْ مِن رَّبِّكَ إِلَىٰٓ أَجَلٍ مُّسَمًّى لَّقُضِىَ بَيْنَهُمْ ۚ وَإِنَّ ٱلَّذِينَ أُورِثُوا۟ ٱلْكِتَـٰبَ مِنۢ بَعْدِهِمْ لَفِى شَكٍّ مِّنْهُ مُرِيبٍ

And they did not become divided until after knowledge had come to them - out of jealous animosity between themselves. And if not for a word that preceded from your Lord [postponing the penalty] until a specified time, it would have been concluded between them. And indeed, those who were granted inheritance of the Scripture after them are, concerning it, in disquieting doubt.