Death Pact

With the last words of power, you make the convert’s oath binding and ensure your deity’s aid when the worst befalls his new servant.

(Spell Compendium, p. 60)  
Originally posted on D&D tools

Necromancy

Level: Cleric 8, Pact 8,
Components: V, S, M, DF,
Casting Time: 10 minutes
Range: Touch
Target: Willing living creature touched
Duration: Permanent until triggered
Saving Throw: None
Spell Resistance: No

This spell allows the target to enter into a binding agreement with your deity that brings the target back to life if it is slain.

When this spell is caste, the subject’s Constitution is permanently lowered by 2 points. In exchange for this, if the subject should die, a true resurrection spell is immediately cast upon the subject. However, the resurrected creature does not regain the 2 Constitution points when returned to life. If the spell is dispelled before the subject dies, it does not regain its lost Constitution points, A wish or miracle spell can return the lost Constitution, but only after the death pact has been activated or dispelled.

Material Component: A diamond worth at least 1,000 gp.