Contradiction with 1 Samuel 15:2-3
God commands Saul to utterly destroy the Amalekites, contradicting the idea of seeking help from Him as 2 Chronicles 20:4 suggests a peaceful petition for assistance.
1 Samuel 15:2-3: Thus saith the LORD of hosts, I remember [that] which Amalek did to Israel, how he laid [wait] for him in the way, when he came up from Egypt.
Contradiction with Matthew 5:44
Instructs to love your enemies and pray for those who persecute you, contrasting with the idea of going to battle or seeking revenge as a solution to threats in 2 Chronicles 20:4.
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 Matthew 26:52
Jesus tells Peter to put away his sword, indicating that those who rely on the sword will perish by it, opposing the concept of mobilizing for war in response to a threat as implied in 2 Chronicles 20:4.
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 James 4:2-3
Suggests that conflicts come from desires and improper asking, contrasting the united asking for help seen in 2 Chronicles 20:4 as a virtuous act.
James 4:2-3: Ye lust, and have not: ye kill, and desire to have, and cannot obtain: ye fight and war, yet ye have not, because ye ask not.