Contradiction with Proverbs 3:5
Judges 18:8 involves a reliance on human planning, while Proverbs 3:5 instructs trust in the Lord and not in one’s understanding.
Proverbs 3:5: Trust in the LORD with all thine heart; and lean not unto thine own understanding.
Contradiction with Matthew 5:44
Judges 18:8 is about the preparation for conquest, which involves violence, whereas Matthew 5:44 urges love for enemies and non-violence.
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
Judges 18:8 suggests taking judgment into one's own hands, while Romans 12:19 advises to leave vengeance to God.
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 James 1:20
Judges 18:8 involves actions that may stem from anger and force, whereas James 1:20 states the wrath of man doesn't produce God's righteousness.
James 1:20: For the wrath of man worketh not the righteousness of God.
Contradiction with Ephesians 4:31
Judges 18:8 involves preparing for actions that include strife, while Ephesians 4:31 instructs to put away anger, malice, and clamor.
Ephesians 4:31: Let all bitterness, and wrath, and anger, and clamour, and evil speaking, be put away from you, with all malice:
Contradiction with Matthew 26:52
Judges 18:8 is about gearing for conflict, opposed by Matthew 26:52 which states those who take up the sword shall perish by it.
Matthew 26:52: Thinkest thou that I cannot now pray to my Father, and he shall presently give me more than twelve legions of angels?
Contradiction with 1 Peter 3:9
Judges 18:8 suggests retaliatory action, while 1 Peter 3:9 advises not to return evil for evil, but to bless instead.
1 Peter 3:9: Not rendering evil for evil, or railing for railing: but contrariwise blessing; knowing that ye are thereunto called, that ye should inherit a blessing.