While churches in GA are still (thankfully) a Gun-Free Zone, the Commonwealth of VA is going in the direction of serious paranoia and is going to allow parishioners to pack heat while worshiping the Prince of Peace. Of course, that also means other religious groups will be able to do the same, like Muslims in their mosques, for example.
Churches may ban weapons like any other private property owner, a good option for sensible people in rational congregations.
What would Jesus do? I don't think he would arm himself since the Bible never mentions he carried a weapon.
We all know the real reason this is even being discussed: the Religious Right has confused conservative politics with religious dogma, and the Good News is no longer abut the peace of Jesus. Instead, it is now an excuse to use the pulpit to postulate a political message of God, Guns and American Glory.
Jesus is the All American Boy, and he has no problem with guns. II Opinions 4:12.