حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ، كَانَ يَأْمُرُ بِتَسْوِيَةِ الصُّفُوفِ فَإِذَا جَاءُوهُ فَأَخْبَرُوهُ أَنْ قَدِ اسْتَوَتْ كَبَّرَ ‏.‏

Yahya related to me from Malik from Nafi that Umar ibn al-Khattabused to order the rows to be straightened, and when they had come tohim and told him that the rows were straight he would say the takbir. Translation Not Available

Book Ref: Muwatta Imam Malik Book 9 Hadith 378
Web Ref:  Muwatta Imam Malik Book 9 Hadith 47

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