Matthew 3:7

But when he saw many of the Pharisees and of the Sadducees coming to his baptism, he said to them, O ye broods of vipers! who hath warned you to flee from the wrath to come?

Matthew 23:33

Ye serpents, ye broods of vipers! how can ye escape from the damnation of hell?

Romans 3:13

Their throat is an open sepulchre; with their tongues they have spoken craftily; the poison of asps is under their lips:

James 3:8

but the tongue can no man tame; it is an unruly evil, full of deadly poison.

Treasury of Scripture Knowledge

Summary

Their poison is like the poison of a serpent: they are like the deaf adder that stoppeth her ear;

Bible References

Poison

Romans 3:13
Their throat is an open sepulchre; with their tongues they have spoken craftily; the poison of asps is under their lips:
James 3:8
but the tongue can no man tame; it is an unruly evil, full of deadly poison.