Nothing can prevent you from completing the task set before you by the gods, not even death.

Daily   ✦     Divine
Immediate Interrupt      Personal

Trigger: An attack reduces you to 0 hit points or fewer and doesn't kill you

Effect: You are dying but don't fall unconscious. Until the end of your next turn, you don't take any damage after the triggering attack, and you gain a +4 bonus to attack rolls. At the end of your next turn, you fall unconscious if you are still dying.

Published in Player's Handbook 2, page(s) 41.