Context. The Law is a civil code. Yes, in ancient Israel a man was not in sin should he use lethal force to protect his home...however, Jesus calls us to a righteousness higher than the Law.
Christ's statement was an illustration that they would face violent opposition. When they brought two swords Jesus rebuked them for taking him literally and said, "It is enough.", meaning, "Stop this now." The next thing we see is Peter using one of these swords to protect Christ in the garden...and Jesus rebukes him.
Context.
Where do you see indication that Jesus rebuked them for taking Him literally and that in fact He did not mean for them to buy swords?
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There are no weapons of mass destruction in Iraq, Chuck Norris lives in Houston.
Either the United States will destroy ignorance, or ignorance will destroy the United States. – W.E.B. DuBois