رِيَاضُ الصَّالِحِينَ
Riyad as-Salihin 823
The Book of the Etiquette of Sleeping, Lying and Sitting etc
Manners of Lying down on one's back and placing one leg upon the Other
وَعَنْ الشريد بْنَ سُوَيْدٍ رضى اَللَّهُ عَنْهُ قَالَ: مَرَّ بِي رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَأَنَا جَالِسٌ هَكَذَا، وَقَدْ وَضَعْتُ يَدِيَ الْيُسْرَى خَلْفَ ظَهْرِي، وَاتَّكَأْتُ عَلَى إلية يَدِي فَقَالَ: أَتَقْعُدُ قِعْدَةَ الْمَغْضُوبِ عَلَيْهِمْ؟! ((رَوَاهُ أَبُو دَاوُدَ بِإِسْنَادٍ صَحِيح)).
Ash-Sharid bin Suwaid (May Allah be pleased with him) reported: Messenger of Allah (ﷺ) passed by me when I was sitting with my left hand behind my back and leaning on my palm. On seeing me in this posture he said, "Do you sit like those upon whom the Wrath of Allah has descended?" [Abu Dawud].
Riyad as-Salihin, 823