Anas ibn Malik reported: The Messenger of Allah, peace and blessings be upon him, said, “Help your brother, whether he is an oppressor or is being oppressed.” It was said, “O Messenger of Allah, we help the oppressed, but how do we help an oppressor?” The Prophet said, “By seizing his hand.”
Source: Ṣaḥīḥ al-Bukhārī 2444
Grade: Sahih (authentic) according to Al-Bukhari
Imam Ibn al-Malak commented, “That is, stop your brother from wronging anyone. Your support for him is that you have pushed him away from sinning, which is the reason he might enter the Hellfire. It is as if you have pushed the Hellfire away from him, and what support is more perfect than pushing the Hellfire away from your brother?”
Source: Sharḥ al-Maṣābīḥ 5/293
عَنْ أَنَسٍ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ انْصُرْ أَخَاكَ ظَالِمًا أَوْ مَظْلُومًا قَالُوا يَا رَسُولَ اللَّهِ هَذَا نَنْصُرُهُ مَظْلُومًا فَكَيْفَ نَنْصُرُهُ ظَالِمًا قَالَ تَأْخُذُ فَوْقَ يَدَيْهِ
2444 صحيح البخاري كتاب المظالم انصر أخاك ظالما أو مظلوما
قال ابن الملك أي منعُك أخاك من أن يظلم أحدًا نصرُك إياه لأنه قد دفعته عن الإثم الذي هو سببُ دخول النار فكأنك دفعت النار عنه وأيُّ نصرة أكملُ من دفع النار عن أخيك
5/293 شرح المصابيح لابن الملك