Contradiction with Matthew 5:44
Numbers 1:20 speaks of counting men able to go to war, emphasizing fighting, while Matthew 5:44 promotes loving 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 Exodus 20:13
Numbers 1:20 involves preparation for war, whereas Exodus 20:13 commands not to kill, discouraging bloodshed.
Exodus 20:13: Thou shalt not kill.
Contradiction with Isaiah 2:4
Numbers 1:20 prepares for war, while Isaiah 2:4 envisions a time when nations will no longer learn war, promoting peace.
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]
Contradiction with Romans 12:19
Numbers 1:20 identifies those available for combat, whereas Romans 12:19 advises against seeking vengeance and leaving it 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.