ibn Umar · The Book of Menstruation

Umar said: Is one amongst us permitted to sleep in a state of impurity (i. e. after having sexual intercourse)? He (the Holy Prophet) said: Yes, after performing ablution.

'Umar asked the verdict of the Shari'ah from the Apostle (ﷺ) thus: Is it permissible for any one of us to sleep in a state of impurity? He (the Prophet said: Yes, he must perform ablution and then sleep and take a bath when he desires.

Umar b. al-Khattab said to the Messenger of Allah (ﷺ), that he became Junbi during the night. The Messenger of Allah (ﷺ) said to him: Perform ablution, wash your sexual organ and then go to sleep.

A person happened to pass by the Messenger of Allah (ﷺ) when he was making water and saluted him, but he did not respond to his salutation.