This quest is not available in game.
Speak to Ur'kyo in Orgrimmar.
It always warms my undying heart to see priests from all cultures wander the world. To know that power exists that is not arcane and well within our grasp. That's why it is my honor to direct you home, <name>.
Ur'kyo, your great priest in Orgrimmar, has asked for your presence. You can find him in the Valley of Spirits.