What is largely unkown about many of the best bands is that they right their music from the perspective of belief. The GOOD stuff is good precisely because it entails an understanding of a topic. The reason it chills the soul is because it is supposed to. Like a good horror story, it is often about the madness that evil entails.
But sometimes the best of the best remove the mask and give clear contrast to the Evil they so often tell of.
Judas Priest did just that with this gorgeous little ditty.
WARNING: LOUD GUITAR SOLOS, SCREAMING, and CHRISTIANITY involved.