[Machine] The Messenger of Allah ﷺ used to pray thirteen rak'ahs at night, in which he would perform the witr prayer with five rak'ahs. He would not sit during any of them until he sat in the last one. According to the narration of Ibrahim ibn Musa, he would conclude his prayer with the saying of "as-salamu alaykum" (peace be upon you). In the narration of Abu Bakr, the prayer of the Messenger of Allah ﷺ at night consisted of thirteen rak'ahs, in which he would perform the witr prayer with five rak'ahs. He would not sit during any of them except for the last one.  

كَانَ رَسُولُ اللهِ ﷺ يُصَلِّي ثَلَاثَ عَشْرَةَ رَكْعَةً يُوتِرُ مِنْهَا بِخَمْسٍ وَلَا يَجْلِسُ فِي شَيْءٍ مِنْهَا حَتَّى يَجْلِسَ فِي آخِرِهِنَّ فَيُسَلِّمَ لَفْظُ حَدِيثِ إِبْرَاهِيمَ بْنِ مُوسَى وَفِي رِوَايَةِ أَبِي بَكْرٍ كَانَتْ صَلَاةُ رَسُولِ اللهِ ﷺ بِاللَّيْلِ ثَلَاثَ عَشْرَةَ رَكْعَةً يُوتِرُ مِنْ ذَلِكَ بِخَمْسٍ لَا يَجْلِسُ فِي شَيْءٍ مِنْهَا إِلَّا فِي آخِرِهَا