The Otherworldly must behave as his stage prescribes, until the power becomes part of him. Until the potion is digested, the bearer is vulnerable: the power is already there, but there is no control over it yet.
The roles of the path are pastoral: the Listener hears what others do not say, the Shepherd is responsible for those who followed him.
The method remained the knowledge of the few for a long time: the church hierarchs were in no hurry to reveal it, and many Otherworldly ascended blindly, paying for it with their sanity.