﴿ فَتَقَطَّعُوٓا۟ أَمْرَهُم بَيْنَهُمْ زُبُرًۭا ۖ كُلُّ حِزْبٍۭ بِمَا لَدَيْهِمْ فَرِحُونَ ﴾

“But they (who claim to follow you) have torn their unity wide asunder, piece by piece, each group delighting in [but] what they themselves possess [by way of tenets].”

But they the followers split into sects regarding their affair their religion zuburan ‘sects’ is a circumstantial qualifier of the subject of the verb taqatta‘ū ‘they split’ in other words they became opposing parties the likes of the Jews and the Christians and others each party rejoicing in exultant with what they had that is with the religion they had.