Surah Ash-Shuraa 42:14

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.

Translation: Saheeh International

Tafsir

And they did not become divided that is the adherents of the monotheistic religions did not become divided in religion — so that some affirmed the Oneness of God while others rejected it — except after the knowledge of His Oneness had come to them out of jealous rivalry on the part of the disbelievers among …

Excerpt from Tafsir al-Jalalayn, commentary on 42:14, via Quran.com. The reader has the full commentary and 9 more tafsirs.