If Jesus allowed Peter to carry a sword for protection, why are the Jehovah's Witnesses against carry a weapon during their "fun" door-to-door adventuring? It seems Jesus did not mind that Peter carried a sword if we read Luke 22:36-38
Jehovah's Witnesses teach that the only reason Jesus wanted his disciples to have swords that night was so he could teach them that they should not have swords:
"When they replied, “Lord, look! here are two swords,” he said to them: “It is enough.” (Luke 22:36-38) Enough for what? First, to fulfill Isaiah 53:12. Secondly, to drive home an important lesson for Christians Surely there could have been no stronger reason for using a sword than protecting the Son of God himself! Yet it was not God’s will for Jesus to be spared at that time. So when the apostle Peter used his sword against the slave of the high priest, Jesus told him: “Return your sword to its place, for all those who take the sword will perish by the sword.” (Matthew 26:52, 53; John 18:10, 11) Jesus thus made it plain that theocratic warfare from that time on was not to include the use of carnal weapons." (The Watchtower July 15, 1983 p. 19)