Sunan Abi Dawud, Hadith 2324

Narrated Ahmad b. 'Abd al-Wahid: On the authority of Abu Mushir. He said: Sa'id, that is, Ibn 'Abd al-'Aziz said: The meaning of the word sirraha is "in the beginning of it (the month)"

حَدَّثَنَا أَحْمَدُ بْنُ عَبْدِ الْوَاحِدِ، حَدَّثَنَا أَبُو مُسْهِرٍ، قَالَ كَانَ سَعِيدٌ - يَعْنِي ابْنَ عَبْدِ الْعَزِيزِ - يَقُولُ سِرُّهُ أَوَّلُهُ ‏.‏ قَالَ أَبُو دَاوُدَ وَقَالَ بَعْضُهُمْ سِرُّهُ وَسَطُهُ وَقَالُوا آخِرُهُ ‏.‏

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also referenced under: Hadith 2331 (DarusSalam)