Divine intervention is strictly a one-time ability for each character, and there aren't any hidden story paths tied to using it multiple times. When you unlock it at level 10, watch for the distinct golden glow animation that appears during the cast - this is your visual confirmation it's working. The ability triggers instantly but you'll want to position your cleric safely since they'll be locked in place during the animation. Maybe interesting to note that while some players try respeccing characters or using hirelings to get extra casts, these are just exploits and won't unlock special content.

After using divine intervention, that character's divine connection is permanently spent, and the game tracks this even through saves. The core story branches depend on your major decisions with companions and factions, so focus your divine intervention for crucial combat moments instead of hunting for secret endings. Your best approach is treating it as the powerful one-shot ability it's designed to be, timing it carefully when you really need that divine backup.