Sunan Abi Dawud, Hadith 4400

Mujahid said: “Apponting a way in the verse (iv.15) means prescribed punishment. Sufiyan said: “Punish them “refers to unmarried, and “confine them to houses” refers to the women who are married.

حَدَّثَنَا أَحْمَدُ بْنُ مُحَمَّدِ بْنِ ثَابِتٍ، حَدَّثَنَا مُوسَى، - يَعْنِي ابْنَ مَسْعُودٍ - عَنْ شِبْلٍ، عَنِ ابْنِ أَبِي نَجِيحٍ، عَنْ مُجَاهِدٍ، قَالَ السَّبِيلُ الْحَدُّ قَالَ سُفْيَانُ ‏{‏ فَآذُوهُمَا ‏}‏ الْبِكْرَانِ ‏{‏ فَأَمْسِكُوهُنَّ فِي الْبُيُوتِ ‏}‏ الثَّيِّبَاتِ ‏.‏

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also referenced under: Hadith 4414 (DarusSalam)