«وَأَذُوبَ وَأَجْمُدَ، وَأَذْكُوَ وَأَخْمُدَ»
And must I melt and freeze, blaze and grow cold?
Dhawb / jumūd juxtapose melting and solidifying, while dhukūw / khumūd evoke a fire rising and dying out. Natural images make the social argument vivid.
The point is that a speaker cannot reasonably be required to become opposites merely to suit the other party's wishes. The balanced syntax makes the objection especially memorable.