SRD:Geas/Quest

A geas places a magical command on a creature to carry out some service or to refrain from some action or course of activity, as desired by you. The creature must be able to understand you. While a geas cannot compel a creature to kill itself or perform acts that would result in certain death, it can cause almost any other course of activity.

The geased creature must follow the given instructions until the geas is completed, no matter how long it takes.

If the instructions involve some open-ended task that the recipient cannot complete through his own actions the spell remains in effect for a maximum of one day per caster level. A clever recipient can subvert some instructions:

If the subject is prevented from obeying the geas for 24 hours, the subject takes 3d6 points of damage each day it does not attempt to follow the geas/quest. Additionally, each day it must make a Fortitude saving throw or become sickened. These effects end 24 hours after the creature attempts to resume the geas/quest.

A remove curse spell ends a geas/quest spell only if its caster level is at least two higher than your caster level. Break enchantment does not end a geas/quest, but limited wish, miracle, and wish do.

Bards, sorcerers, and wizards usually refer to this spell as geas, while clerics call the same spell quest.