There are three things which are a taste of the World to Come: Shabbat, the sun, and “usage.” What does “usage” mean? Usage of the bed [i.e. marital relations]? But that weakens the body. Rather it means usage of the orifices [i.e. emptying one’s bowels].
Talmud Bavli, Berachot 57b
How can the pleasure of the afterlife be equated with using the bathroom? Is this an example of “humor in the Talmud?”