Nudo detrahere vestimenta quis potest?
(Plautus, Asinaria 92)

Pron = NOO-doh day-TRA-heh-reh wes-tih-MEHN-tah kwis POH-test.

Who is able to take away the clothes from the naked?

Comment: this is the equivalent of "You cannot get blood out of turnips", or "you cannot give what you don"t have", or more bluntly:
"you"ll get it when I have it".

There is some real honesty in this kind of saying. For those who would try to do what they really have no ability to do, it is an invitation to be honest about that. For those who would abuse the poor or those caught in a bad place, it is a warning to see more clearly.

If a man or woman is naked, you cannot take his/her clothes because of a debt owed to you.

I"ve had to confront a student or two recently about missing work or lack of effort (at all). I think it was the right thing to do, given the circumstances, but reflecting on this proverb leaves me wondering: due to circumstances that I know nothing about, are they left with nothing to give, nothing to draw on" Are they the "naked" that I am asking clothing from" The bottom line is that I don"t know.

Considering the possibility humbles me.