Musnad Ahmad Hadith 23352

Tha’laba bin Zahdam says that once we were in Tabaristan with Sa’eed bin Aas (may Allah be pleased with him). He asked the people, “Who among you has performed the Salat al-Khawf (prayer of fear) with the Prophet Muhammad (ﷺ)?” Hudhaifah (may Allah be pleased with him) replied, “I have, and it was like this: the people formed two rows behind the Prophet Muhammad (ﷺ). One row stood facing the enemy, and one row stood behind the Prophet Muhammad (ﷺ) for prayer. The Prophet Muhammad (ﷺ) led them in one rak’ah, then these people walked backwards to the place of those who were standing facing the enemy, and those people came and stood behind the Prophet Muhammad (ﷺ) in their place. The Prophet Muhammad (ﷺ) then led them in the second rak’ah, and then the Prophet Muhammad (ﷺ) said the salam (ending the prayer). In this way, the Prophet Muhammad (ﷺ) completed two rak’ahs, and each group behind him performed one rak’ah.”