He used to become sexually impure at night, then he would want to sleep. The Messenger of Allah told him to perform ablution and then go to sleep.
أَنْ يَنَامَ فَأَمَرَهُ رَسُولُ اللَّهِ ﷺ أَنْ يَتَوَضَّأَ ثُمَّ يَنَامَ
[Machine] Abu Sa'id Al-Khudri mentioned to the Messenger of Allah ﷺ that he experiences impurity (janabah) and intends to sleep. So, he commanded him to perform ablution (wudu) and then sleep.
أَنَّ أَبَا سَعِيدٍ الْخُدْرِيَّ ذَكَرَ لِرَسُولِ اللهِ ﷺ أَنَّهُ تُصِيبُهُ الْجَنَابَةُ فَيُرِيدُ أَنْ يَنَامَ فَأَمَرَهُ أَنْ يَتَوَضَّأَ ثُمَّ يَنَامَ