Gun ownership and usage
Gun ownership. To what extent might a believer in Christ defend himself against the physical threats to himself or his loved ones in this world today?
It is the “to what extent” phrase of your question that requires individual and conscientious application of biblical principles.
Some Christians look to Matthew 5:39 and Romans 12:17 as absolute directives not to resist physical threats. In their context though the verses advocate love toward others instead of seeking revenge.
Others look to sections of Scripture like Proverbs 24:11-12 and Luke 22:35-38 as the basis for defending oneself and one’s family from physical threats. The second reference does inform us that the disciples were lightly armed. John 18:10-11 describes Peter’s wrongful use of one of those weapons as he tried to interfere with the Lord’s humble submission to his Father’s will. The positive emphasis of the Fourth Commandment “to help and befriend [our neighbor] in every bodily need” can find application in defending oneself and one’s family with a weapon.
But, again, it’s the “to what extent” phrase that individual Christians will need to address. There are governmental laws controlling the purchase and usage of guns. There are legally-mandated gun-free zones and right to carry laws. Christians will seek to recognize and honor Fourth Commandment and Fifth Commandment principles and navigate through life showing love to God and others.