1. If the enemy is not in the direction of the qiblah, then the imam should lead a group in the performance of one rak’ah after which he should wait until they complete the second rak’ah by themselves, and then, they should go and face the enemy. And the second group should come and the imam would lead them in salah while he is performing his second rak’ah. He should again wait for them to complete another rak’ah by themselves before leading them in the salutations.
Saleh ibn Khawat relates from Saleh ibn Abu Khaithimah that a group lined up with the Prophet sallallahu alehi wasallam while another group faced the enemy. He prayed one rak’ah with the group that was with him and remained standing while they finished the salah and left and faced the enemy. The second group came and prayed the remaining rak’ah with him, then he stayed sitting until they had completed their prayers individually, after which he led them in making the taslim. This is related by the group, except for Ibn Majah.
2. If the enemy is not in the direction of the qiblah, then, the imam prays one rak’ah with one group of the army while the other group faces the enemy, after which the two groups exchange places, and the imam prays one rak’ah with the second group. The members of each group will complete one rak’ah of their prayers on their own.
Ibn ‘Umar says: “The Messenger of Allah prayed one rak’ah with one group while the other group faced the enemy, [At that point, those who had prayed] took the place of their companions facing the enemy and the second group came and prayed one rak’ah with the Prophet and then he made the taslim. Then each group made (the remaining) one rak’ah.” This is related by al-Bukhari, Muslim, and Ahmad. It is apparent that the second group completed their salah after the imam made the taslim without discontinuing their salah (i.e. for them, it was two continuous rak’at), and the first group did not complete their salah until the second group had completed their salah and went back to face the enemy. Ibn Mas’ud says: “Then, he made the taslim and they stood up to finish the second rak’ah individually and, then they made their taslim.”
3. The imam prays two rak’at with each group, the first two rak’at being his fard salah and the latter two being nafl. It is allowed for one who is making a nafl to lead others in salah who are praying fard. Jabir reports that the Prophet prayed two rak’at with one group of his companions and then another two rak’at with another group and then he made the taslim. This is related by ash-Shaf’i and an-Nasa’i.
Abu Dawud, Ahmad, and an-Nasa’i record that he said: “The Prophet prayed the salatul Khauf with us, and he prayed two rak’at with some of his companions, and then the others came and took their places and he prayed two rak’at with them, and he made the taslim. So, the Prophet prayed four rak’at and the people prayed two rak’at each.”
Ahmad, al-Bukhari, and Muslim record that he said: “We were with the Prophet during the campaign of Zhat al-Riqa and the salah was made, and he prayed two rak’at with one group and then they withdrew, and he led the other group in two rak’at. The Prophet prayed four rak’at and the people prayed two rak’at.”
4. If the enemy is in the direction of the qiblah, then the imam leads both of the groups in salah at the same time and they share in guarding against the enemy, and they follow the imam in every one of his actions until he performs sajdah, in which case one group will make the sajdah with him and the other will wait until they are finished and then perform their own sujjud. After the first rak’ah is finished, the people in front will move to the back and those in the back will move to the front.
Jabir said: “I prayed salatul khauf (fear prayer) with the Prophet. He arranged us in two rows behind him. The enemy was between us and the qiblah. The Prophet sallallahu alehi wasallam made the takbir and we all made the takbir. He performed the ruku’ and we all made the ruku’. Then, he raised his head from the ruku’ and we all raised our heads from the ruku’. Next he went down for sajdah as well as the row closest to him, while the back row stood facing the enemy until the Prophet and the first row had completed their prostrations, after which the back row made sajdah and then stood [after completing their sajjud]. Following this, those in the back row moved to the front while those in the front row moved to the back. The Prophet performed the ruku’ and we all made ruku’. Then, he raised his head and we raised our heads from ruku. Afterward, he made the sajdah and the row that was previously in the back during the first rak’ah prostrated with him while the [new] back row stood facing the enemy. When the Prophet and the [new] front row had completed their sujjud, the [new] back row made the sujjud. Finally, the Prophet made the taslim and we all made the taslim. This is related by Ahmad, Muslim, an-Nasa’i, Ibn Majah, and al-Baihaqi.
5. Both of the groups begin the prayer with the imam, and then one group would guard against the enemy while the other group would pray one rak’ah with the imam, after which they would face the enemy while the other group would come and pray one rak’ah by themselves (individually) while the imam is standing. Then, they would join him in what is the imam’s and their second rak’ah. At that point, the group which had gone to face the enemy would come and pray one rak’ah (their second) individually while the others would be sitting (in salah waiting for them to sit in their second rak’ah), after which the imam would make the taslim and both groups would make the taslim together [behind the imam].
Abu Huraira reports: “I prayed salatul khauf with the Messenger of Allah during the year of the Battle of Najd. He stood to pray ‘asr and one group stood with him while the other group was faced the enemy with their backs toward the qiblah. When he made the takbir, all the people made the takbir- that is, those with him and those facing the enemy. Then, he performed one rak’ah and the group with him also performed their ruku’ and sujjud with him while the others were still facing the enemy. Next, the group which was with the Prophet went to face the enemy while the other group came and prayed one rak’ah and the Prophet kept standing [in prayer] as he was. Then, he performed the ruku’ and the new group performed the ruku’ with him and he performed the sajdah and they performed the sajdah with him. After this, the group which had gone to face the enemy came and prayed one rak’ah while the Prophet and those with him were sitting [in prayer]. Finally, the Prophet made taslim and both groups made the taslim with him. The Prophet prayed two rak’at and both groups prayed two rak’at.” This is related by Ahmad, Abu Dawud, and an-Nasa’i.
6. Each group prays only one rak’ah with the imam and the imam prays a total of two rak’at whereas each group prays one. Ibn ‘Abbas reports that the Prophet prayed at Zhi-qard, and he arranged the people into two rows, one row behind him and one row guarding against the enemy. The group behind him prayed one rak’ah (with him) and then left the place to the other group. The other group then came and prayed one rak’ah (with the Prophet), and [neither group] made up a rak’ah. This is related by anNasa’i and Ibn Hibban. Ibn ‘Abbas also says: “Allah made the prayer obligatory on your Prophet [in the following manner]: four rak’at while resident, two while traveling, and only one during times of fear.” This is related by Ahmad, Muslim, Abu Dawud, and an-Nasa’i.