Contradiction with Matthew 5:44
Jeremiah 50:30 speaks of vengeance and destruction, while Matthew 5:44 teaches love for enemies and praying for those who persecute you, contradicting the idea of executing judgment.
Matthew 5:44: But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you;
Contradiction with Romans 12:19
Jeremiah 50:30 depicts the Lord's direct vengeance, whereas Romans 12:19 advises leaving vengeance to God and not taking revenge personally.
Romans 12:19: Dearly beloved, avenge not yourselves, but [rather] give place unto wrath: for it is written, Vengeance [is] mine; I will repay, saith the Lord.
Contradiction with Ezekiel 33:11
Jeremiah 50:30 discusses the downfall and death of the enemy, which contrasts with Ezekiel 33:11 where God expresses no pleasure in the death of the wicked, but prefers they turn from their ways and live.
Ezekiel 33:11: Say unto them, [As] I live, saith the Lord GOD, I have no pleasure in the death of the wicked; but that the wicked turn from his way and live: turn ye, turn ye from your evil ways; for why will ye die, O house of Israel?