Christians Should Buy Swords

The Bible is filled with instances of violence and this leaves many Christians questioning what is appropriate for those who follow Christ today in relation to using violence. I recently asked folks about how they make sense of Jesus' use of a whip in his cleansing of the temple. Another passage that I've heard many brothers and sisters reference as a justification for the use of violence by Christians is Jesus' command for the disciples to buy swords. 

And he said to them, “When I sent you out with no moneybag or knapsack or sandals, did you lack anything?” They said, “Nothing.” He said to them, “But now let the one who has a moneybag take it, and likewise a knapsack. And let the one who has no sword sell his cloak and buy one. For I tell you that this Scripture must be fulfilled in me: 'And he was numbered with the transgressors.’ For what is written about me has its fulfillment.” And they said, “Look, Lord, here are two swords.” And he said to them, “It is enough” (Luke 22:35-38).

I'm curious as to how, in the eyes of some, Jesus' command for the disciples promotes or gives permission for Christians today to use violence against other humans in self defense, defense of others, and/or war. Anyone who examines this passage and it's implications for Christian ethics regarding the use of violence would do well to ask the following questions:

1) What is reasonable to conclude about the reason for the command given by Jesus according to surrounding scriptures (specifically Luke 22:49-53, Matthew 26:51-56, Mark 14:46-50, John 18:10-11, Isaiah 53:12), church tradition, cultural context, etc.?

2) If any type of violent activity is promoted/approved by this passage, how is that action defined (what are it's limitations) and what type of violence does it allow for present day Christians to use? What does it not allow?

3) If Jesus is promoting the use of certain violent action for particular purposes then how does that promotion compliment the teachings by Jesus regarding peace, nonresistance, mercy, forgiveness, etc. and does that promotion compliment his work on the cross? 

If you believe Jesus' command for the disciples to buy swords contributes to the allowance of Christians to employ violence against other humans I'd be interested in hearing your answers to these questions. If you comment with your answer I will not meet it with hostility or argument. At most, I will ask follow-up questions for the sake of clarity or elaboration (if it is welcomed). 

Please share this with your friends so we can collect some great answers and perhaps start some edifying dialogues. For reading, commenting, sharing, thinking, thank you.