Is a man sinful if he buries his wife on the night of cohabitation, and what is the wisdom behind not burying on this night?

It is permissible for a husband to bury his wife, even if he has recently engaged in intercourse. However, it is preferable for someone who has not engaged in intercourse that night to undertake the burial, if such a person is available. This is based on the hadith (definition) narrated by Anas in Sahih (definition) al-Bukhari concerning the burial of the Prophet's daughter (peace be upon him), where he said: "Which of you did not have intercourse tonight?" Abu Talha replied, "I did not." He (the Prophet) said, "Then descend into her grave."

Some scholars are of the view that preferring someone who has not recently engaged in intercourse applies when strangers are equal in their characteristics. The wisdom behind this is to ensure the person is in a state of humility and modesty, and further removed from remembering worldly matters and their departure. There is no sin upon one who has had intercourse with his wife and then undertaken the burial.