"The Messenger of Allah ﷺ was camping between Dajnan and 'Usfan, besieging the idolaters. The idolaters said: 'These people have a prayer that is dearer to them than their sons and daughters. Plan it, then strike them with a single heavy blow.' Jibril, peace be upon him, came and told the Messenger of Allah ﷺ to divide his companions into two groups, then lead one group in prayer while the others faced the enemy, on guard and with weapons at the ready. So he led them in praying one rak'ah, then they moved back and the others moved forward, and he led them in praying on rak'ah, so that each one of them had prayed one rak'ah with the Prophet ﷺ and the Prophet ﷺ had prayed two rak'ahs." (Using translation from Nasāʾī 1544)
كَانَ رَسُولُ اللهِ ﷺ نَازِلًا بَيْنَ ضَجْنَانَ وَعُسْفَانَ يُحَاذِي الْمُشْرِكِينَ فَقَالَ الْمُشْرِكُونَ إِنَّ لِهَؤُلَاءِ صَلَاةً هِيَ أَهَمُّ إِلَيْهِمْ مِنِ أَبْنَائِهِمْ وَأَبْكَارِهِمِ أَجْمِعُوا أَمْرَكُمْ ثُمَّ مِيلُوا عَلَيْهِمْ مَيْلَةً وَاحِدَةً فَجَاءَ جِبْرِيلُ فَأَمَرَهُ أَنْ يُقَسِّمَ أَصْحَابَهُ نِصْفَيْنِ يُصَلِّي بِطَائِفَةٍ مِنْهُمْ وَطَائِفَةٌ مُقْبِلُونَ عَلَى عَدُوِّهِمْ قَدْ أَخَذُوا حِذْرَهُمْ وَأَسْلِحَتَهُمْ فَيُصَلِّي بِهِمْ رَكْعَةً ثُمَّ يَتَأَخَّرُ هَؤُلَاءِ وَيَتَقَدَّمُ أُولَئِكَ فَيُصَلِّي بِهِمْ رَكْعَةً تَكُونُ لَهُمْ مَعَ النَّبِيِّ ﷺ رَكْعَةٌ رَكْعَةٌ وَلِلنَّبِيِّ ﷺ رَكْعَتَانِ