يَا أَيُّهَا الَّذِينَ آمَنُوا إِذَا تَنَاجَيْتُمْ فَلَا تَتَنَاجَوْا بِالْإِثْمِ وَالْعُدْوَانِ وَمَعْصِيَتِ الرَّسُولِ وَتَنَاجَوْا بِالْبِرِّ وَالتَّقْوَى وَاتَّقُوا اللَّهَ الَّذِي إِلَيْهِ تُحْشَرُونَ
O you who have faith! When you converse secretly, do not hold private conversations [imbued] with sin and aggression and disobedience to the Apostle, but converse in [a spirit of] piety and Godfearing, and be wary of Allah toward whom you will be gathered.
Agha Ali Puya Commentary
Commentary on Quran 58:9
[Pooya/Ali Commentary 58:9] Believers are forbidden to take part in any secret movement to spread evil and terror. They must work for righteousness with self-restraint.