"Ibn Jarhad informed me from his father, that the Prophet ﷺ passed by him while his thigh was exposed, so the Prophet ﷺ said: 'Cover your thigh, for indeed it is 'Awrah.'"
أَنَّ النَّبِيَّ ﷺ مَرَّ بِهِ وَهُوَ كَاشِفٌ عَنْ فَخِذِهِ فَقَالَ النَّبِيُّ ﷺ غَطِّ فَخِذَكَ فَإِنَّهَا مِنَ الْعَوْرَةِ