Sunan An-Nasa'i

It was narrated from Ya'la that the Messenger of Allah (ﷺ) saw a man performing Ghusl in an open place, so he ascended the Minbar and praised and glorified Allah, then he said:'Allah, the Mighty and Sublime, is forbearing, modest and concealing, and He loves modesty and concealment. When any one of you performs Ghusl, let him conceal himself