When casting, the spell can be centered at any point in the air within the range, or upon a single object. If cast upon an object, the light moves with that object. It cannot be cast on a creature or person.

Once cast, the spell generates a soft white light, which protects a spherical area up to 20' in radius.

For characters and creatures other than evil and undead, the brightness of the light can be as dim as candlelight or as bright as torchlight, as desired by the caster. To evil and undead, however, the light always appears piercingly bright, and causes them great pain to look at the light or remain within the protected area.

Any evil and undead creatures within the protected area suffer 1 point of holy damage per caster level each round, and suffer a -1 penalty to their attack rolls and saving throws for every 4 levels of the caster. Each round they remain in the area, they must succeed on a Will save (Save vs. Spell in 2nd Ed), or are forced to flee the protected area. Creatures driven out in this manner are unable to willingly re-enter the protected area, but may be forced back into the area if the protected area moves with an object.

Evil and undead creatures outside of the protected area must make a successful save in order to attack characters within the protected area, or to cast spells in the direction of the protected area. Failing their save means they are driven back, or lose their concentration.

The material components for this spell are the priest's holy symbol and a purified white candle. The candle is expended in the casting.