Another thought on Christ’s command to be armed: this command is one of multiple cases where Christ prophetically preempts great heresies that would be wickedly attached to his name.
Perhaps the foremost example was when he said, “Think not that I am come to destroy the law or the prophets”. No prophet that he had sent previously had to say, “I’m not replacing what was said before me”; yet one of the greatest heresies that would be later taught is that we can ignore, downplay, and disobey everything God said before he came to earth. It’s almost like Christ knew this beforehand. 🤔
Similarly, no prophet Christ had sent previously needed to teach people the importance of the duty of being armed and ready to fight (except perhaps in certain cases, such as “cursed be he that keepeth back his sword from blood” Jer 48). The sudden emphasis Christ places on this duty was no doubt prompted by the knowledge that in future one of the great heresies would be to blasphemously associate the name of Christ with pagan concepts of blanket non-violence.
Some such ideas of pacifism no doubt were wormed into the cultural view of Christianity via the Roman Catholics, who were simply dressed up pagans from the start. But wherever such ideas came from, they are obviously utterly incompatible with Christianity.
One dramatic example of this incompatibility is when some rationalise pacifism by saying that we should not protect ourselves (or even others!) because this is a lack of faith in God’s protection. This is all but straight from the mouth of Satan, who said to Christ, “Cast thyself down, for it is written, He shall give his angels charge concerning thee”, and of course the same answer is given to the pacifists as Christ gave to Satan: “It is written, Thou shalt not test the Lord thy God.”
All Christians have the duty to be ready to fight as well as they can to defend others as they defend themselves (they should defend themselves), and to avenge others, as they would have others avenge them.