Abjure

When a cleric employs a spell of this sort, he or she is attempting to return a creature from another plane of existence to its own plane. 

The exact name of the type of creature to be affected by the abjure spell must be known. If the creature also has a specific (proper) name, then that too must be known and used. 

The naming cleric then compares his or her level against the level or hit dice of the creature under abjuration, in the same way that the success of a dispel magic spell is determined (base 50% chance of success, plus or minus the level/HD difference between the caster and the creature to be affected). The percent chance for success is then compared to a percentile dice roll. If the roll is equal to or less than the chance to abjure, the creature is instantly sent back to its own plane. In all other cases the spell fails. (The creature might not wish to remain on the caster's plane, and in such a case it could be appreciative of the cleric's attempt to return it to its home.)

The material components for an abjure spell are a holy/unholy symbol, holy or unholy water, and often some material inimical to the creature. 

The reverse of this spell, implore, entreats some like-aligned creature from another plane to come to the cleric casting the spell. 

Success must be determined just as if abjure had been cast. In like vein, the spell caster must know the exact name of the type of creature as well as its given name, if any. 

If the implore spell succeeds, the cleric has absolutely no guarantee that the creature summoned from another plane will be favorably disposed to him or her. Neither version of the spell will function upon deities, but might affect servants or minions thereof.

In reversed form, the material components are the same except for the last, which must be something that the implored creature craves or respects.