Mark 7:21-22
For from within, out of people's hearts, proceed evil thoughts, sexual immorality, stealing, murder, extramarital affairs,
Matthew 10:33
But whoever disowns me in front of people [i.e., denies that I am the Christ, or that he is a disciple. See John 18:15-17, 25-27], I will disown him in front of my Father in heaven.
Matthew 12:34-36
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.
Acts 5:3-4
But Peter said to Ananias, "Why has Satan filled your heart [causing you] to deceive the Holy Spirit by keeping back part of the selling price of the land [while representing it as the full price]?
Romans 3:10-18
as it is written [Psa. 14:1ff; 53:1ff], "No one [always] does what is right; not even one person.
Titus 1:16
These people claim to know God [as Savior], but they deny Him by their actions, so they are detestable and disobedient and unfit for doing anything good.
Hebrews 3:12
Pay attention, brothers, so that there will not be in any one of you an evil heart of unbelief, [resulting] in falling away from the living God.
James 1:15
Then, when the evil desire has conceived, it gives birth to sin. And when sin is fully grown, it produces [spiritual] death.
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].