Mishkat al-Masabih
Abu Sa'id al-Khudri reported God’s Messenger as saying, "When three are on a journey they should appoint one of them as their commander.” Abu Dawud transmitted it.
وَعَنْ أَبِي سَعِيدٍ الْخُدْرِيُّ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «إِذَا كَانَ ثَلَاثَةٌ فِي سَفَرٍ فَلْيُؤَمِّرُوا أحدهم» . رَوَاهُ أَبُو دَاوُد
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