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malik:9-83Mālik > Rabīʿah b. Abū ʿAbd al-Raḥman

Yahya related to me from Malik from Rabia ibn Abi Abd ar-Rahman that if Abdullah ibn Umar arrived at the mosque and the people had already prayed, he would begin with the obligatory prayer and not pray anything before it.  

مالك:٩-٨٣وَحَدَّثَنِي عَنْ مَالِكٍ عَنْ رَبِيعَةَ بْنِ أَبِي عَبْدِ الرَّحْمَنِ

أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ كَانَ إِذَا جَاءَ الْمَسْجِدَ وَقَدْ صَلَّى النَّاسُ بَدَأَ بِصَلاَةِ الْمَكْتُوبَةِ وَلَمْ يُصَلِّ قَبْلَهَا شَيْئًا