Matthew 12:34

You children of snakes! Since you are evil, how do you expect to speak good things? For the mouth speaks what the heart is filled with.

Romans 3:13-14

[Psa. 5:9 says], "Their throats are like open graves [i.e., they are foul-mouthed]. They have spoken deceitfully." [Psa. 90:3 says], "There is snake venom under their lips [i.e., their words are deadly]."

2 Corinthians 11:3

But I am afraid that somehow, just as the snake tricked Eve by his cunning, your minds might [also] be led astray from your sincere and pure devotion to Christ.

James 3:6-8

And the tongue is [like] a fire [i.e., like that spark]. [For] the tongue, as a part of the body, is [like] the world of evil. It corrupts the entire life [of a person] and inflames the course of nature itself [i.e., it affects a person throughout his whole earthly existence], and is ignited by hell itself [i.e., the evil produced by the fiery tongue has hell as its source and destiny].

Treasury of Scripture Knowledge

Summary

They have sharpened their tongues like a serpent; adders' poison is under their lips. Selah.

Sharpened

Adders

Bible References

Sharpened

James 3:6
And the tongue is [like] a fire [i.e., like that spark]. [For] the tongue, as a part of the body, is [like] the world of evil. It corrupts the entire life [of a person] and inflames the course of nature itself [i.e., it affects a person throughout his whole earthly existence], and is ignited by hell itself [i.e., the evil produced by the fiery tongue has hell as its source and destiny].

Like a serpent

Matthew 12:34
You children of snakes! Since you are evil, how do you expect to speak good things? For the mouth speaks what the heart is filled with.
2 Corinthians 11:3
But I am afraid that somehow, just as the snake tricked Eve by his cunning, your minds might [also] be led astray from your sincere and pure devotion to Christ.

Adders

Romans 3:13
[Psa. 5:9 says], "Their throats are like open graves [i.e., they are foul-mouthed]. They have spoken deceitfully." [Psa. 90:3 says], "There is snake venom under their lips [i.e., their words are deadly]."