Hallow makes a particular site, building, or structure a holy site. This has four major effects.

First, the site is warded by a magic circle against evil effect. All creatures within the area gain the effects of a protection from evil spell, and evil summoned creatures cannot enter the area either. Creatures in the area, or who later enter the area, receive only one attempt to suppress effects that are controlling them. If successful, such effects are suppressed as long as they remain in the area. Creatures that leave the area and come back are not protected. You must overcome a creature's spell resistance in order to keep it at bay (as in the third function of protection from evil), but the deflection and resistance bonuses and the protection from mental control apply regardless of enemies' spell resistance.

Second, the DC to resist positive channeled energy within this area gains a +4 sacred bonus and the DC to resist negative energy is reduced by 4. Spell resistance does not apply to this effect. This provision does not apply to the druid version of the spell.

Third, any dead body interred in a hallowed site cannot be turned into an undead creature.

Finally, you can fix a single spell effect to the hallowed site. The spell effect lasts for 1 year and functions throughout the entire site, regardless of the normal duration and area or effect. You may designate whether the effect applies to all creatures, creatures who share your faith or alignment, or creatures who adhere to another faith or alignment. At the end of the year, the chosen effect lapses, but it can be renewed or replaced simply by casting hallow again.

Spell effects that may be tied to a hallowed site include aid, bane, bless, cause fear, darkness, daylight, death ward, deeper darkness, detect evil, detect magic, dimensional anchor, discern lies, dispel magic, endure elements, freedom of movement, invisibility purge, protection from energy, remove fear, resist energy, silence, tongues, and zone of truth. Saving throws and spell resistance might apply to these spells' effects. (See the individual spell descriptions for details.)

An area can receive only one hallow spell (and its associated spell effect) at a time. Hallow counters but does not dispel unhallow.