What is the meaning of leather straps in the hadith?

Question

I came upon this quote and don't understand the meaning of it. The translation and commentary are even more confusing. Please help:

The Messenger of Allah ﷺ said: The eyes are the leather strap of the anus, so one who sleeps should perform ablution.

Source

Answer 1

Wudu (ablution) is a ritual of washing the hands, arms, face, head and feet. It is required to be performed as a pre-requisite of certain acts such as before performing Salah (ritual worship). Performing wudu creates a state of cleanliness in which the acts can be performed, and the state gets 'broken' by certain 'nullifies of wudu' such as urinating, defecating and passing gas. Once wudu is broken a person becomes unclean and hence needs to re-perform wudu when he again needs to do something that requires being in a clean state.

Wudu is also considered broken when one falls asleep (there are different schools of thought on this but I am not going to cover that as that does not seem to be the intent of your question). So for example if you perform wudu and then fall sleep and then wake up, you can no longer perform worship rituals unless you redo the wudu.

This hadith is part of the evidence for the ruling that sleep breaks wudu as it tells us to renew wudu after falling sleeping, and gives a reason for that ruling. The reason is that a sleeping person becomes unconscious and so is unsure of whether he has passed gas and hence broken his wudu and to be certain he must redo the wudu. Saying that "The eyes are the leather strap of the anus" is a way of conveying that he can not be sure of whether he has passed gas.