Tha'labah ibn Zahdam said: We accompanied Sa'd ibn al-'As at Tabaristan. He stood and said: Which of you prayed along with the Messenger of Allah ﷺ in time of danger? Hudhayfah said: I then he led one section in one rak'ah and the other section in one rak'ah. They did not pray the second rak'ah by themselves. Abu Dawud: This tradition has been transmitted by 'Ubaid Allah b. 'Abd Allah and Mujahid on the authority of Ibn 'Abbas from the Prophet ﷺ in like manner. This has also been narrated by 'Abd Allah b. Shaqiq from Abu Hurairah from the Prophet ﷺ. Yazid al-Faqir and Abu Musa also narrated this tradition from Jabir from the Prophet ﷺ. Some of the narrators said in the version narrated by Yazid al-Faqir that they completed their second rak'ah. This has also been narrated by Simak al-Hanafi on the authority of Ibn 'Umar from the Prophet ﷺ something similar. Zaid b. Thabit also narrated from the Prophet ﷺ in like manner. This version adds: The people prayed on rak'ah and the Prophet ﷺ prayed two rak'ahs.  

أَيُّكُمْ صَلَّى مَعَ رَسُولِ اللَّهِ ﷺ صَلاَةَ الْخَوْفِ فَقَالَ حُذَيْفَةُ أَنَا فَصَلَّى بِهَؤُلاَءِ رَكْعَةً وَبِهَؤُلاَءِ رَكْعَةً وَلَمْ يَقْضُوا  

Allah, the Exalted, prescribed prayer for you, through the tongue of your Prophet ﷺ, four rak'ahs while resident, two rak'ahs while travelling and one rak'ah in time of danger.  

فَرَضَ اللَّهُ تَعَالَى الصَّلاَةَ عَلَى لِسَانِ نَبِيِّكُمْ ﷺ فِي الْحَضَرِ أَرْبَعًا وَفِي السَّفَرِ رَكْعَتَيْنِ وَفِي الْخَوْفِ رَكْعَةً