“The Prophet (ﷺ) came out
to
pray and said the Takbir, then he gestured to them to wait. He went
and took a bath, and his head was dripping with water while he led
them in prayer. When he finished he said: ‘I came out to you in a
state of sexual impurity, and I forgot until I had started to pray.’”
Sunan Ibn Majah Book 5, Hadith 418