'Poison' in the Bible

They will take up snakes, and if there is poison in their drink, it will do them no evil; they will put their hands on those who are ill, and they will get well.

Their throat is like an open place of death; with their tongues they have said what is not true: the poison of snakes is under their lips:

But the tongue may not be controlled by man; it is an unresting evil, it is full of the poison of death.