Very Steven King (Reminded me most of ‘Storm of the Century’). The juxtaposition of religious and horror myths is clever.
I suppose the final implication is that the preacher "mistook" a vampire for an angel, but in the fictional context, I'm not entirely sure he was originally mistaken, and I'm almost disappointed with the resolution suggesting he was (a change of heart which is abrupt and unearned). Of course the idea that devils have bat wings and angels are beautiful doves isn't anywhere in the bible, but angels are instead described as frightening monsters (like the preacher says). And I further can't remember any biblical passages where the devil can bestow any special powers like resurrection. Instead powers always come from God. So in the a universe where we assume Christianity is true and vampires exist, I think it actually makes a lot more sense to interpret these creatures as some sort of divine beings instead of Satanic ones.