Contradiction with Jeremiah 17:9
This verse suggests that the human heart is deceitful, implying that people can harbor lies internally, contradicting 1 John 2:21 which states that knowing the truth negates having a lie.
Jeremiah 17:9: The heart [is] deceitful above all [things], and desperately wicked: who can know it?
Contradiction with Proverbs 20:9
This verse questions the ability of anyone to claim a pure heart, suggesting inherent deception, in contrast to 1 John 2:21's implication of possessing truth without lies.
Proverbs 20:9: Who can say, I have made my heart clean, I am pure from my sin?
Contradiction with Psalm 116:11
The psalmist claims all men are liars, which contradicts the assertion in 1 John 2:21 that knowing the truth means having no lies.
Psalm 116:11: I said in my haste, All men [are] liars.
Contradiction with Romans 3:4
This verse states that every man is a liar, opposing the statement in 1 John 2:21 where the truth excludes lies.
Romans 3:4: God forbid: yea, let God be true, but every man a liar; as it is written, That thou mightest be justified in thy sayings, and mightest overcome when thou art judged.
Contradiction with 1 John 1:8
This suggests self-deception in claiming to be without sin, challenging 1 John 2:21 by indicating that self-professed truth isn't free of lies.
1 John 1:8: If we say that we have no sin, we deceive ourselves, and the truth is not in us.