Contradiction with Isaiah 2:4
This verse speaks of turning swords into plowshares and not learning war anymore, contrasting the wielding of a sword in Ezekiel 21:9.
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 Matthew 26:52
This verse suggests that those who take up the sword will perish by it, contradicting the action of drawing the sword in Ezekiel 21:9.
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 Micah 4:3
Similar to Isaiah 2:4, this verse discusses beating swords into plowshares, contradicting the preparation for war in Ezekiel 21:9.
Micah 4:3: And he shall judge among many people, and rebuke strong nations afar off; and they shall beat their swords into plowshares, and their spears into pruninghooks: nation shall not lift up a sword against nation, neither shall they learn war any more. [pruninghooks: or, scythes]
Contradiction with Zechariah 9:10
This verse speaks of removing the battle bow and proclaiming peace to the nations, contradicting the sharpening of a sword in Ezekiel 21:9.
Zechariah 9:10: And I will cut off the chariot from Ephraim, and the horse from Jerusalem, and the battle bow shall be cut off: and he shall speak peace unto the heathen: and his dominion [shall be] from sea [even] to sea, and from the river [even] to the ends of the earth.