Abu Dawud

Narrated Al-Miswar bin Makhramah: I lifted a heavy stone. While I was walking my garment fell down. The Messenger of Allah ﷺ said to me: Take you garment upon you, and do not walk naked.

Bahz bin Hakim said that his father told on the authority of his grandfather: I said: Messenger of Allah, from whom should we conceal our private parts and to whom can we show? He replied: conceal your private parts except from your wife and from whom your right hands possess (slave-girls). I then asked: Messenger of Allah, (what should we do), if the people are assembled together? He replied: If it is within your power that no one looks at it, then no one should look at it. I then asked: Messenger of Allah if one of us is alone, (what should he do)? He replied: Allah is more entitled than people that bashfulness should be shown to him.

Narrated Abu Saeed al-Khudri: The Prophet ﷺ said: A man should not look at the private parts of another man, and a woman should not look at the private parts of another woman. A man should not lie with another man without wearing lower garment under one cover; and a woman should not be lie with another woman without wearing lower garment under one cover.

Narrated Abu Hurairah: The Prophet ﷺ said: A man should not lie with another man and a woman should not lie with another woman without covering their private parts except a child or a father. He also mentioned a third thing which I forgot.