I think it's ok to carry and use weapons. Jesus's disciples carried and used one, for defense against wild animals mainly I think, and possibly robbers etc. But it's important not to live by it. I.e. don't put your trust in it over God, it's a last resort. I think they would have called on the name of Jesus first before drawing any weapons. The interesting thing is that Jesus said he could have called angels to help him when Peter cut the guys ear off. Jesus probably didn't carry any sort of sword. So yes, faith, is probably a bit contradictary to carrying a weapon if we trust in the weapon more than God. Maybe we should call on God's angels for help first.