As a Christian, I've had to work a couple of these things out in my mind before becoming a gun owner, and a concealed carry weapons permit holder. As a good Christian citizen, I follow Romans 13:1–6 (among other texts) as a guide for submission to government authority. In America, we are blessed as citizens with many constitutional freedoms that are granted in our government's founding documents, one of which includes the 2nd Amendment. So, in some (limited) way, our Constitution has afforded U.S. citizens with the right to "wield the sword," at least in limited cases of self-defense, family defense, and personal defense. So, even before God, I believe my conscience is clear in my commitment and resolve to take personal and home defense seriously. If I'm attacked, or my home is broken into, I'm willing to defend myself, my family, and my home as far as the law allows. That is a blessing from our Constitution, and it's consistent with the relevant passages in the Bible that address submission to governing authorities. In other words, I see the 2nd Amendment as a wise Constitutional provision made to U.S. citizens that help make our human "unalienable" rights something that we can defend should they come under attack.
I'm not a gun-nut. I don't have stockpiles of ammo and dozens of guns in my house (although I would love to have some more guns!). I mostly don't think that our government is out to get us (though some gun owners do think that way), and I'm pretty much a realist that, even if they were out to get us, it probably wouldn't go well for us—you know, private citizens with their small weapons and the government with their big weapons. We probably wouldn't win in a SHTF situation. The world has changed quite a bit since the days of the Revolution and the Civil War. In my mind, many of the changes that have happened have actually been pretty good.
So yes, I own guns for self-defense, and I've done my best to think through why I think it's a good idea to own guns and to use them for defense, should an extreme situation occur. But that's not the only reason I own guns. I also just enjoy them as a hobby. I've made many friends since getting into guns and learning to shoot. I've enjoyed hunting with family friends, and it's given me opportunities to get to know some of those friends better. It's a fun and enjoyable hobby. If you play things smart, it won't cost more than golf. And for me, things that go "bang" (guns) are more fun than things that go "whack" (golf).