An-Nisa' - 4:102

وَإِذَا كُنتَ فِيهِمْ فَأَقَمْتَ لَهُمُ الصَّلاَةَ فَلْتَقُمْ طَآئِفَةٌ مِّنْهُم مَّعَكَ وَلْيَأْخُذُواْ أَسْلِحَتَهُمْ فَإِذَا سَجَدُواْ فَلْيَكُونُواْ مِن وَرَآئِكُمْ وَلْتَأْتِ طَآئِفَةٌ أُخْرَى لَمْ يُصَلُّواْ فَلْيُصَلُّواْ مَعَكَ وَلْيَأْخُذُواْ حِذْرَهُمْ وَأَسْلِحَتَهُمْ وَدَّ الَّذِينَ كَفَرُواْ لَوْ تَغْفُلُونَ عَنْ أَسْلِحَتِكُمْ وَأَمْتِعَتِكُمْ فَيَمِيلُونَ عَلَيْكُم مَّيْلَةً وَاحِدَةً وَلاَ جُنَاحَ عَلَيْكُمْ إِن كَانَ بِكُمْ أَذًى مِّن مَّطَرٍ أَوْ كُنتُم مَّرْضَى أَن تَضَعُواْ أَسْلِحَتَكُمْ وَخُذُواْ حِذْرَكُمْ إِنَّ اللّهَ أَعَدَّ لِلْكَافِرِينَ عَذَابًا مُّهِينًا
[4:102]
And when you are among them and keep up the prayer for them, let a party of them stand up with you, and let them take their arms; then when they have prostrated themselves let them go to your rear, and let another party who have not prayed come forward and pray with you, and let them take their precautions and their arms; (for) those who disbelieve desire that you may be careless of your arms and your luggage, so that they may then turn upon you with a sudden united attack, and there is no blame on you, if you are annoyed with rain or if you are sick, that you lay down your arms, and take your precautions; surely Allah has prepared a disgraceful chastisement for the unbelievers.
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.
And when thou (O Muhammad) art among them and arrangest (their) worship for them, let only a party of them stand with thee (to worship) and let them take their arms. Then when they have performed their prostrations let them fall to the rear and let another party come that hath not worshipped and let them worship with thee, and let them take their precaution and their arms. Those who disbelieve long for you to neglect your arms and your baggage that they may attack you once for all. It is no sin for you to lay aside your arms, if rain impedeth you or ye are sick. But take your precaution. Lo! Allah prepareth for the disbelievers shameful punishment.