The Messenger of Allah ﷺ saw a man washing in a public place without a lower garment. So he mounted the pulpit, praised and extolled Allah and said: Allah is characterised by modesty and concealment. So when any of you washes, he should conceal himself.  

أَنَّ رَسُولَ اللَّهِ ﷺ رَأَى رَجُلاً يَغْتَسِلُ بِالْبَرَازِ بِلاَ إِزَارٍ فَصَعِدَ الْمِنْبَرَ فَحَمِدَ اللَّهَ وَأَثْنَى عَلَيْهِ ثُمَّ قَالَ ﷺ إِنَّ اللَّهَ ﷻ حَيِيٌّ سِتِّيرٌ يُحِبُّ الْحَيَاءَ وَالسَّتْرَ فَإِذَا اغْتَسَلَ أَحَدُكُمْ فَلْيَسْتَتِرْ  

The former is more perfect.  

عَنِ النَّبِيِّ ﷺ بِهَذَا الْحَدِيثِ  

The Messenger of Allah ﷺ sat with us and my thigh was uncovered. He said: Do you not know that thigh is a private part ?  

كَانَ جَرْهَدٌ هَذَا مِنْ أَصْحَابِ الصُّفَّةِ قَالَ جَلَسَ رَسُولُ اللَّهِ ﷺ عِنْدَنَا وَفَخِذِي مُنْكَشِفَةٌ فَقَالَ أَمَا عَلِمْتَ أَنَّ الْفَخِذَ عَوْرَةٌ  

The Prophet ﷺ said: Do not uncover you thigh, and do not look at the thigh of the living and the dead. Abu Dawud said: This tradition disagrees with the generally reported traditions (nakarah).  

قَالَ رَسُولُ اللَّهِ ﷺ لاَ تَكْشِفْ فَخِذَكَ وَلاَ تَنْظُرْ إِلَى فَخِذِ حَىٍّ وَلاَ مَيِّتٍ