Sunan Abi Dawud, Hadith 2330

Sulaiman b. 'Abd al-Rahman al-Dimashqi said about this tradition that al-Walid said: I heard Abu 'Amr al-Auza'i say: The word sirrahu means beginning of the month.

حَدَّثَنَا سُلَيْمَانُ بْنُ عَبْدِ الرَّحْمَنِ الدِّمَشْقِيُّ، - فِي هَذَا الْحَدِيثِ - قَالَ قَالَ الْوَلِيدُ سَمِعْتُ أَبَا عَمْرٍو - يَعْنِي الأَوْزَاعِيَّ - يَقُولُ سِرُّهُ أَوَّلُهُ ‏.‏

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also referenced under: Hadith 2323 (Hasan)