حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، وَأَحْمَدُ بْنُ عَمْرِو بْنِ السَّرْحِ، - وَهَذَا لَفْظُهُ - قَالاَ حَدَّثَنَا سُفْيَانُ، عَنِ الزُّهْرِيِّ، عَنْ عَطَاءِ بْنِ يَزِيدَ اللَّيْثِيِّ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ، أَنَّ النَّبِيَّ صلى الله عليه وسلم نَهَى عَنْ بَيْعَتَيْنِ وَعَنْ لِبْسَتَيْنِ أَمَّا الْبَيْعَتَانِ فَالْمُلاَمَسَةُ وَالْمُنَابَذَةُ وَأَمَّا اللِّبْسَتَانِ فَاشْتِمَالُ الصَّمَّاءِ وَأَنْ يَحْتَبِيَ الرَّجُلُ فِي ثَوْبٍ وَاحِدٍ كَاشِفًا عَنْ فَرْجِهِ أَوْ لَيْسَ عَلَى فَرْجِهِ مِنْهُ شَىْءٌ ‏.‏

Narrated Abu Sa’id Al Khudri : The Prophet (PBUH) forbade two types of business transactions and two ways of dressing. The two types of business transactions are mulamasah and munabadhah. As regards the two ways of dressing, they are the wrapping of the samma', and that when a man wraps himself up in a single garment while sitting in such a way that he does not cover his private parts or there is no garment on his private parts. Translation Not Available

Book Ref: Sunan Abi Dawud Book 23 Hadith 3377
Web Ref:  Sunan Abi Dawud Book 22 Hadith 3371