When using this spell, the priest renders his mind completely immune to any mind-affecting spell, power, or psionic effect. This includes amnesia, awe, beguiling, charm, command, confusion, domination, emotion, empathy, ESP, fascination, fear, feeblemind, hold, hypnotism, insanity, magic jar, mind blast, phantasmal killer, possession, rulership, sleep, soul trapping, suggestion, telepathy, and any psionic attack or power of the telepathic discipline. In short, if the spell or effect coerces the priest into taking an action or forming an impression that he doesn't wish to, it fails while impervious sanctity of mind is in effect. The only mind-affecting spells or powers that can affect the protected priest are those of exceedingly powerful creatures or artifacts and relics.
Unlike the wizard spell mind blank, the impervious sanctity of mind offers no protection against detection or scrying. However, it is effective against some attacks and powers that mind blank is powerless against. The spell requires a small ring of lead that was once breathed upon by a red dragon.