Bible Verses About Unbelief: Was an impediment to the performance of miracles

And Jesus said unto them, Because of your unbelief: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you.

And he could there do no mighty work, save that he laid his hands upon a few sick folk, and healed them.