So we ought to ask for more suffering, start enjoying it? I don't like these sadistic paradigms.
Suffering is a call for some true action on your part.

good point ... so its basically a mercy from individual self-decadence then !? - so you suffer, "deplete yourself", in a way, to stop yourself from "depleting" in another. ;)

Rumi's point being suffering can make real men (or women, didn't mean to sound sexist ;)) out of us.

It can make us stronger individuals since you learn and adapt to tough situations. In the process you could learn more about yourself.. it could give you an insight into your strengths/weaknesses. And finally make you appreciate what you otherwise took for granted.

so it can humble you, force you to develop patience, make you appreciative/thankful, & finally a better and stronger person. Indeed a mercy then...

that said its all in a "could" sense, the chickens among us would just raise hell all day and feed on ample self-supplied depression ;)

i cant understand the bit about mercy actually.
is it gods gift and mercy that he allows us to suffer and therefore advance?

And the part about mercy? I find that I work myself just as hard, if not harder, each time I go back.

i "suffer" every time i go the gym or put in my lengths at the swimming pool. but God it feels good afterwards!
as brad pitt says in fight club - "self improvement is masterbation"