My father and I went to `Aisha and she said, "I testify that Allah's Messenger (ﷺ) at times used to get up in
the morning in a state of Janaba from sexual intercourse, not from a wet dream and then he would fast
that day." Then he went to Um Salama and she also narrated a similar thing.
Sahih al-Bukhari Book 30, Hadith 39