Sahih Bukhari

Narrated Abu Bakr bin `Abdur-Rahman: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