﴿ كَانُوا۟ لَا يَتَنَاهَوْنَ عَن مُّنكَرٍۢ فَعَلُوهُ ۚ لَبِئْسَ مَا كَانُوا۟ يَفْعَلُونَ ﴾

“They would not prevent one another from doing whatever hateful things they did: vile indeed was what they were wont to do!”

(They restrained not one another) they did not repent (from the wickedness) the evil actions (they did. Verily evil was that they used to do!) evil are the sins and transgressions they used to engage in.