وَإِذَا كُنتَ فِيهِمۡ فَأَقَمۡتَ لَهُمُ ٱلصَّلَوٰةَ فَلۡتَقُمۡ طَآئِفَةٌ مِّنۡهُم مَّعَكَ وَلۡيَأۡخُذُوٓاْ أَسۡلِحَتَهُمۡ فَإِذَا سَجَدُواْ فَلۡيَكُونُواْ مِن وَرَآئِكُمۡ وَلۡتَأۡتِ طَآئِفَةٌ أُخۡرَىٰ لَمۡ يُصَلُّواْ فَلۡيُصَلُّواْ مَعَكَ وَلۡيَأۡخُذُواْ حِذۡرَهُمۡ وَأَسۡلِحَتَهُمۡ ۗ وَدَّ ٱلَّذِينَ كَفَرُواْ لَوۡ تَغۡفُلُونَ عَنۡ أَسۡلِحَتِكُمۡ وَأَمۡتِعَتِكُمۡ فَيَمِيلُونَ عَلَيۡكُم مَّيۡلَةً وَٰحِدَةً ۚ وَلَا جُنَاحَ عَلَيۡكُمۡ إِن كَانَ بِكُمۡ أَذًى مِّن مَّطَرٍ أَوۡ كُنتُم مَّرۡضَىٰٓ أَن تَضَعُوٓاْ أَسۡلِحَتَكُمۡ ۖ وَخُذُواْ حِذۡرَكُمۡ ۗ إِنَّ ٱللَّهَ أَعَدَّ لِلۡكَٰفِرِينَ عَذَابًا مُّهِينًا
When thou (O Messenger) art with them, and standest to lead them in prayer, Let one party of them stand up (in prayer) with thee, Taking their arms with them: When they finish their prostrations, let them Take their position in the rear. And let the other party come up which hath not yet prayed - and let them pray with thee, Taking all precaution, and bearing arms: the Unbelievers wish, if ye were negligent of your arms and your baggage, to assault you in a single rush. But there is no blame on you if ye put away your arms because of the inconvenience of rain or because ye are ill; but take (every) precaution for yourselves. For the Unbelievers Allah hath prepared a humiliating punishment.<br/>
When you, O Muhammad may peace and salutation be upon him, are, present, among them, while you [all] fear an enemy, and you stand to lead them in prayer (this type of address is customary in Al-Qur'an), let a party of them stand with you, while another party stand back, and let them, the party standing with you, take their weapons, with them. Then when they have performed their prostrations, that is, [when] they have prayed, let them, the other party, be behind you, on guard until you complete the prayers; thereupon, let this party go on guard, and let another party who have not prayed come and pray with you, taking their precautions and their weapons, with them until you have completed the prayers. The Prophet may peace and salutation be upon him did this once at Batn Nakhla, as reported by the two Shaykhs [Bukhaaree and Muslim]. The disbelievers wish, when you have stood up to pray, that you should be heedless of your weapons and your baggage that they may descend upon you all at once, by making an assault against you and capturing you, and herein is the reasoning behind keeping weapons on oneself. You are not at fault, if rain bothers you, or if you are sick, to lay aside your weapons, and not carry them: this implies that when there is no such excuse, it is compulsory to carry them, and this is one of two opinions held by al-Shaafi'ee [on this matter]; the other [opinion] is that this [precaution] constitutes a sunna, and this is the more preferable opinion. But take your precautions, against the enemy and be on your guard as best you can; God has prepared for the disbelievers a humiliating chastisement.