The Messenger of Allah ﷺ forbade that a man should lie placing(and according to Qutaibah’s version: “should raise”) one of his legs over the other. Qutaibah’s version adds: When he was lying on his back.  

نَهَى رَسُولُ اللَّهِ ﷺ أَنْ يَضَعَ وَقَالَ قُتَيْبَةُ يَرْفَعَ الرَّجُلُ إِحْدَى رِجْلَيْهِ عَلَى الأُخْرَى زَادَ قُتَيْبَةُ وَهُوَ مُسْتَلْقٍ عَلَى ظَهْرِهِ  

‘Abbad b. Tamim quoted his paternal uncle as saying that he had seen the Messenger of Allah ﷺ lying on his back in the mosque according to Qa’nabi’s version) placing one foot over the other.  

وَحَدَّثَنَا الْقَعْنَبِيُّ عَنْ مَالِكٍ عَنِ ابْنِ شِهَابٍ عَنْ عَبَّادِ بْنِ تَمِيمٍ عَنْ عَمِّهِ أَنَّهُ رَأَى رَسُولَ اللَّهِ ﷺ مُسْتَلْقِيًا قَالَ الْقَعْنَبِيُّ فِي الْمَسْجِدِ وَاضِعًا إِحْدَى رِجْلَيْهِ عَلَى الأُخْرَى  

‘Umar b. al-khattab and ‘Uthman b. ‘Affan used to do that.  

أَنَّ عُمَرَ بْنَ الْخَطَّابِ ؓ وَعُثْمَانَ بْنَ عَفَّانَ كَانَا يَفْعَلاَنِ ذَلِكَ