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malik:9-14Mālik > Nāfiʿ > Sālim b. ʿAbdullāh

Yahya related to me from Malik from Nafi from Salim ibn Abdullah that Abdullah ibn Umar rode to Dhat an-Nusub and shortened the prayer on the journey. Malik said, "There are four mail-stages between Dhat an-Nusub and Madina."  

مالك:٩-١٤حَدَّثَنِي عَنْ مَالِكٍ عَنْ نَافِعٍ عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ

أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ رَكِبَ إِلَى ذَاتِ النُّصُبِ فَقَصَرَ الصَّلاَةَ فِي مَسِيرِهِ ذَلِكَ قَالَ مَالِكٌ وَبَيْنَ ذَاتِ النُّصُبِ وَالْمَدِينَةِ أَرْبَعَةُ بُرُدٍ