True Believer( Magic Item Compendium, p. 222)
Your deity rewards your unquestioning faith and devotion.
Must be within 1 step of that deities alignment, Must Choose a single deity to worship,
Once per day when you are about to attempt a saving throw you can declare that you are using this feat to gain a +2 on the roll. This feat also allows you to use a relic of the diety you worship without sacrificing a spell slot.