Luke 22:35,36 Jesus asked them, When I sent you WITHOUT purse, bag or sandals, did you lack anything? Nothing, they answered. He said to them, But now if you have a purse, take it, and also a bag; and if you don't have a sword, sell your cloak and buy one.
This instruction was not a license to kill. The life is in the blood. If anyone sheds the blood of a man by man shall his blood be shed.
The sword they were instructed to carry was for protection, a deterent. To wound an enemy attacking you preserves life, however we pray, deliver us from every evil attack.
As for a gun, the sword of today? It depends on the reason you would own one. For hunting? Sure! Its humane and a kindness to kill an animal swiftly for food.
When I was young a cat came into our yard and was killing chicks in nests in our trees. I trapped that cat in our wood pile and in my hand I held a pellet rifle capable of killing it. But I saw the cats fear then, and rather than shooting it between the eyes I shot it in the tail splitting the tip in two. The cat was just doing what cats do! That cat never returned. Its life was preserved. Even to this day I cannot bring myself to kill an animal except a fish or bird for food and I hope I never have to.
How could one who has received such a precious gift as Jesus' blood even consider shedding the blood of a man to kill for any reason!!!