[Machine] Abu Bakr used to instruct his governors, when he would send them out during apostasy, that if you come across a house and hear the call to prayer, then hold off until you ask them why they rebelled. But if you do not hear the call to prayer, then attack, kill, burn, and expend all efforts in killing and wounding, with no concern for weakness in causing death to your Prophet ﷺ.  

كَانَ أَبُو بَكْرٍ ؓ يَأْمُرُ أُمَرَاءَهُ حِينَ كَانَ يَبْعَثُهُمْ فِي الرِّدَّةِ إِذَا غَشِيتُمْ دَارًا فَإِنْ سَمِعْتُمْ بِهَا أَذَانًا بِالصَّلَاةِ فَكُفُّوا حَتَّى تَسْأَلُوهُمْ مَاذَا نَقَمُوا فَإِنْ لَمْ تَسْمَعُوا أَذَانًا فَشُنُّوهَا غَارَةً وَاقْتُلُوا وَحَرِّقُوا وَانْهَكُوا فِي الْقَتْلِ وَالْجِرَاحِ لَا يُرَى بِكُمْ وَهَنٌ لِمَوْتِ نَبِيِّكُمْ ﷺ  

[Machine] Abu Bakr used to command his officials when he sent them to fight apostates, saying: "If you reach a town that is fortified, mention this hadith until you reach the following part: 'So set it on fire, kill and fight fiercely in combat. Do not flee or weaken in the face of death for your Prophet.'"  

كَانَ أَبُو بَكْرٍ ؓ يَأْمُرُ أُمَرَاءَهُ حِينَ كَانَ يَبْعَثُهُمْ فِي الرِّدَّةِ إِذَا غَشِيتُمْ دَارًا فَذَكَرَ الْحَدِيثَ إِلَى أَنْ قَالَ فَشُنُّوهَا غَارَةً فَاقْتُلُوا وَأَحْرِقُوا وَانْهَكُوا فِي الْقَتْلِ وَالْجِرَاحِ لَا يُرَى بِكُمْ وَهَنٌ لِمَوْتِ نَبِيِّكُمْ ﷺ