The priest using this spell causes a summoned creature of evil nature, an evil creature from another plane, or a creature summoned by an evil caster, to return to its own plane or place when the caster successfully strikes it in melee combat. Examples of such creatures are aerial servants, djinn, efreet, elementals, and invisible stalkers. An evil enchantment (such as a charm spell cast by an evil creature) that is subject to a normal dispel magic spell can be automatically dispelled by the dispel evil spell. This spell lasts for a maximum of one round for each experience level of the caster, or until expended. While the spell is in effect, all creatures that could be affected by it fight with a -7 penalty to their attack rolls when engaging the spellcaster.
The reverse of the spell, dispel good, functions against summoned or enchanted creatures of good alignment or creatures that have been sent to aid the cause of good.
The material components for this spell are the priest's religious object and holy (or unholy) water.
Notes: Common for clerics (PHB).
High-Level Campaigns Book Addition
Dispel Evil: In addition to driving away evil extra-planar and summoned creatures, this spell is effective against evil enchantment/charm spells and all forms of domination and possession.