BAYHAQI 4825:
from ʿAbd al-Raḥman b. Jubayr b. Nufayr —
[Machine] On the authority of Thawban, the freed slave of the Messenger of Allah ﷺ , who said: "We were with the Messenger of Allah ﷺ during a journey, and he said about this journey, 'It is tiring and burdensome. When any one of you observes the last prayer of the night, let him perform two units of prayer (rak'ahs) before Witr (the final prayer of the night). If he wakes up (in the last part of the night), otherwise they will be counted for him.' The Imam (may Allah, the Most High, have mercy on him) said: It is possible that what is meant by it is two units of prayer after Witr, and it is also possible that what is meant is if he wants to perform Witr, then let him perform two units of prayer before it."
البيهقي ٤٨٢٥:
عن عبد الرحمن بن جبير بن نفير —
عَنْ ثَوْبَانَ مَوْلَى رَسُولِ اللهِ ﷺ قَالَ كُنَّا مَعَ رَسُولِ اللهِ ﷺ فِي سَفَرٍ فَقَالَ فِي هَذَا السَّفَرِ جَهْدٌ وَثُقْلٌ فَإِذَا أَوْتَرَ أَحَدُكُمْ فَلْيَرْكَعْ رَكْعَتَيْنِ فَإِنِ اسْتَيْقَظَ وَإِلَّا كَانَتَا لَهُ قَالَ الْإِمَامُ رَحِمَهُ اللهُ تَعَالَى يَحْتَمِلُ أَنْ يَكُونَ الْمُرَادُ بِهِ رَكْعَتَانِ بَعْدَ الْوِتْرِ وَيَحْتَمِلُ أَنْ يَكُونَ أَرَادَ فَإِذَا أَرَادَ أَنْ يُوتِرَ فَلْيَرْكَعْ رَكْعَتَيْنِ قَبْلَ الْوِتْرِ
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