As-Salat at the time of besieging a fort and at the time of meeting the enemy

وَقَالَ الأَوْزَاعِيُّ إِنْ كَانَ تَهَيَّأَ الْفَتْحُ، وَلَمْ يَقْدِرُوا عَلَى الصَّلاَةِ صَلَّوْا إِيمَاءً كُلُّ امْرِئٍ لِنَفْسِهِ، فَإِنْ لَمْ يَقْدِرُوا عَلَى الإِيمَاءِ أَخَّرُوا الصَّلاَةَ، حَتَّى يَنْكَشِفَ الْقِتَالُ أَوْ يَأْمَنُوا، فَيُصَلُّوا رَكْعَتَيْنِ، فَإِنْ لَمْ يَقْدِرُوا صَلَّوْا رَكْعَةً وَسَجْدَتَيْنِ، لاَ يُجْزِئُهُمُ التَّكْبِيرُ وَيُؤَخِّرُوهَا حَتَّى يَأْمَنُوا وَبِهِ قَالَ مَكْحُولٌ. وَقَالَ أَنَسٌ حَضَرْتُ عِنْدَ مُنَاهَضَةِ حِصْنِ تُسْتَرَ عِنْدَ إِضَاءَةِ الْفَجْرِ، وَاشْتَدَّ اشْتِعَالُ الْقِتَالِ، فَلَمْ يَقْدِرُوا عَلَى الصَّلاَةِ، فَلَمْ نُصَلِّ إِلاَّ بَعْدَ ارْتِفَاعِ النَّهَارِ، فَصَلَّيْنَاهَا وَنَحْنُ مَعَ أَبِي مُوسَى، فَفُتِحَ لَنَا. وَقَالَ أَنَسٌ وَمَا يَسُرُّنِي بِتِلْكَ الصَّلاَةِ الدُّنْيَا وَمَا فِيهَا.Al-Auza'i said, "If there are signs of victory and it is impossible to offer the Salat (prayer) then everyone should offer his Salat (prayer) with signs. If he cannot do even that then he can delay the Salat (prayer) till the battle is over or till they feel secure, then they can offer two Rak'at prayers. But if they are unable to complete the Salat (prayer) then they can perform one bowing and two prostrations (one Rak'a), and if they are unable to do even this, then saying Allahu-Akbar is not sufficient for them, and so they should postpone the Salat (prayer) till they feel secure." Mak-hul agrees to it (i.e. this verdict). And Anas bin Malik said, "I reached at dawn during the siege of Tustar and the fighting was at its peak. The Muslims were not able to offer the Fajr prayer and we did not offer Salat (prayer) till a part of the day had passed and then we offered the Salat with Abu Musa and we were granted victory by Allah." Anas further said, "It would not make me happy even if I got the whole world and whatever is in it instead of that Salat (prayer) (i.e. the one they missed because of fighting)." ​​