كَمَآ أَنزَلۡنَا عَلَى ٱلۡمُقۡتَسِمِينَ
like that We sent down upon those who split into bands,
Agha Ali Puya Commentary
Commentary on Quran 15:90
[Pooya/Ali Commentary 15:90] These verses refer to the Jews and Christians who took out of the scriptures what suited them and ignored or rejected the rest See Al Baqarah: 85 and 101.