وَإِذَا كُنتَ فِيهِمۡ فَأَقَمۡتَ لَهُمُ ٱلصَّلَوٰةَ فَلۡتَقُمۡ طَآئِفَةٞ مِّنۡهُم مَّعَكَ وَلۡيَأۡخُذُوٓاْ أَسۡلِحَتَهُمۡۖ فَإِذَا سَجَدُواْ فَلۡيَكُونُواْ مِن وَرَآئِكُمۡ وَلۡتَأۡتِ طَآئِفَةٌ أُخۡرَىٰ لَمۡ يُصَلُّواْ فَلۡيُصَلُّواْ مَعَكَ وَلۡيَأۡخُذُواْ حِذۡرَهُمۡ وَأَسۡلِحَتَهُمۡۗ وَدَّ ٱلَّذِينَ كَفَرُواْ لَوۡ تَغۡفُلُونَ عَنۡ أَسۡلِحَتِكُمۡ وَأَمۡتِعَتِكُمۡ فَيَمِيلُونَ عَلَيۡكُم مَّيۡلَةٗ وَٰحِدَةٗۚ وَلَا جُنَاحَ عَلَيۡكُمۡ إِن كَانَ بِكُمۡ أَذٗى مِّن مَّطَرٍ أَوۡ كُنتُم مَّرۡضَىٰٓ أَن تَضَعُوٓاْ أَسۡلِحَتَكُمۡۖ وَخُذُواْ حِذۡرَكُمۡۗ إِنَّ ٱللَّهَ أَعَدَّ لِلۡكَٰفِرِينَ عَذَابٗا مُّهِينٗا

Wa izaa kunta feehim fa aqamta lahumus Salaata faltaqum taaa'ifatum minhum ma'aka wal ya'khuzoo aslihatahum fa izaa sajadoo fal yakoonoo minw waraaa'ikum wal ta'ti taaa'ifatun ukhraa lam yusalloo falyusallo ma'aka wal ya'khuzoo hizrahum wa aslihatahum; waddal lazeena kafaroo law taghfuloona 'anaslihatikum wa amti'atikum fa yameeloona 'alaikum mailatanw waahidah; wa laa junaaha 'alaikum in kaana bikum azam mimmatarin aw kuntum mardaaa an tada'ooo aslihatakum wa khuzoo hizrakum; innal laaha a'adda lilkaafireena 'azaabam muheenaa

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.

— An-Nisa' (ٱلنِّسَاء), 4:102