Bible Verses About Unbelief: Questioning the power of God

Then one of the lords, upon whose hand the king leaned, answering the man of God, said: If the Lord should make flood-gates in heaven, can that possibly be which thou sayest? And he said: Thou shalt see it with thy eyes, but shalt not eat thereof.

Yea, they spake against God; they said, Can God furnish a table in the wilderness?

Behold, he smote the rock, that the waters gushed out, and the streams overflowed; can he give bread also? can he provide flesh for his people?