Brother Gaius said, one needs to undergo a test to learn the skill of revival.
#Speak to Gaius in Elim Church and ask to learn the Revival skill.
#Talk to River and purchase Crystalline Stones.
#Speak to Weird Cleric outside of Elim Church and he will send you into a room with two other priests, Albion & Martia.
#Speak to Albion and choose option 2 and say yes. You will be warped into a room with Hariel if you choose "Yes"
#Defeat Hariel and you should receive a Stone in place of one of your Crystalline Stone. Killing it once is enough. All 3 of you will get the stone needed.
##Note:
##Priest class gets Human Stone
##Jobs with melee attack get Earth Stone
##Jobs with ranged attack get Heaven Stone
##You need 1 each of the 3 stones listed above.
##Hence, its advisable that you bring a warrior/knight/craft and mage/jester/hunter to do this quest with you.
##You must be in a party of 3. The people who have done this quest cannot get the stone again.
#Talk to Albion to learn the Revival skill when you have 3 stones.
#Speak to Martia to leave the room.