Contradiction with Matthew 5:39
Contradicts by advocating non-retaliation and turning the other cheek, whereas Judges 7:20 describes a military attack.
Matthew 5:39: But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also.
Contradiction with Exodus 14:14
Contradicts by advising to hold peace and let God fight, unlike Judges 7:20 where people actively engage in battle.
Exodus 14:14: The LORD shall fight for you, and ye shall hold your peace.
Contradiction with Romans 12:19
Encourages leaving vengeance to God, contrasting with the active warfare in Judges 7:20.
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 Isaiah 2:4
Speaks of turning swords into plowshares, conflicting with the battle context of Judges 7:20.
Isaiah 2:4: And he shall judge among the nations, and shall rebuke many people: and they shall beat their swords into plowshares, and their spears into pruninghooks: nation shall not lift up sword against nation, neither shall they learn war any more. [pruninghooks: or, scythes]