These words mean almost the same thing. The writer uses them both to emphasize that the Israelites did not believe that God would either provide for them or punish evil as he had said he would. (See: [[rc://en/ta/man/translate/figs-doublet]])
They wanted God to prove that he could do what he said he would do before they would believe him. See how you translated this idea in [Psalms 78:18](../078/018.md).