‘Ali burned some people who retreated from Islam. When Ibn ‘Abbas was informed of it, he said: If it had been I, I would not have burned them, for the Messenger of Allah ﷺ said: Do not inflict Allah’s punishment on anyone, but would have had killed them on account of the statement of the Messenger of Allah ﷺ. The Apostle said: Kill those who change their religion. When ‘Ali was informed about it he said: How truly Ibn ‘Abbas said!
أَنَّ عَلِيًّا عَلَيْهِ السَّلاَمُ أَحْرَقَ نَاسًا ارْتَدُّوا عَنِ الإِسْلاَمِ فَبَلَغَ ذَلِكَ ابْنَ عَبَّاسٍ فَقَالَ لَمْ أَكُنْ لأَحْرِقَهُمْ بِالنَّارِ إِنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ تُعَذِّبُوا بِعَذَابِ اللَّهِ وَكُنْتُ قَاتِلَهُمْ بِقَوْلِ رَسُولِ اللَّهِ ﷺ فَإِنَّ رَسُولَ اللَّهِ ﷺ قَالَ مَنْ بَدَّلَ دِينَهُ فَاقْتُلُوهُ فَبَلَغَ ذَلِكَ عَلِيًّا عَلَيْهِ السَّلاَمُ فَقَالَ وَيْحَ ابْنَ عَبَّاسٍ