Sunan Abi Dawud, Hadith 4159

Sa'id b. Jubair said: There is no harm in fastening the hair with silk or woollen threads. Abu Dawud said: It appears that he held the view that what is prohibited is the adding of the hair of women. Abu Dawud said: Ahmad (b. hanbal) used to say: There is no harm in tying the hair with silk or woollen threads.

حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرِ بْنِ زِيَادٍ، قَالَ حَدَّثَنَا شَرِيكٌ، عَنْ سَالِمٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، قَالَ لاَ بَأْسَ بِالْقَرَامِلِ ‏.‏ قَالَ أَبُو دَاوُدَ كَأَنَّهُ يَذْهَبُ إِلَى أَنَّ الْمَنْهِيَّ، عَنْهُ شُعُورُ النِّسَاءِ ‏.‏ قَالَ أَبُو دَاوُدَ كَانَ أَحْمَدُ يَقُولُ الْقَرَامِلُ لَيْسَ بِهِ بَأْسٌ ‏.‏

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also referenced under: Hadith 4171 (DarusSalam)