'Unreliable' in the Bible

Men are nothing but a mere breath; human beings are unreliable. When they are weighed in the scales, all of them together are lighter than air.

They were unfaithful and acted as treacherously as their ancestors; they were as unreliable as a malfunctioning bow.

You despise all who stray from your statutes, for they are deceptive and unreliable.