If you look at the version in the DT, the man comes in saying all these things that she has to do, and the woman responds with her own list of impossibilities that he has to do, and she says in effect 'when you've done all that, I'll meet you and hand you your shirt'.

I've always interpreted that verse as try to dry this shirt on this very scratchy bush without breaking all the threads, since there's nothing soft on the bush to prevent the thorns getting at it.

I wonder if this was originally a riddle song on the same lines as the one that goes "give me a cherry without a stone" or whatever it is. And we just lost the verses where it all was explained.

It could also be about the impossible trials that people often require of each other in order to prove they love the person.

~*sirepseh*~