This spell prevents creatures within the area of effect (or those who enter it) from speaking any deliberate and knowing lies. Creatures are allowed a saving throw to avoid the effects; those who fail the save are affected fully. Affected characters are aware of this enchantment; therefore, they may avoid answering questions to which they would normally respond with a lie or they may be evasive as long as they remain within the boundaries of the truth. When a character leaves the area, he is free to speak as he chooses.
The spell affects a square whose sides are five feet long per level of the caster; thus, a 4th-level priest could affect a 20 foot by 20 foot square.
The material components are the priest's holy symbol and a phony emerald, ruby, or diamond.