Who do you usually promote to prophet?

[Graeme Dice]

Originally posted by Saber Cherry:
Level 4 holy is incredibly valuable, simply due to Divine Blessing and (most important) Fanaticism. If only you could force-cast Fanaticism... still... it is the most important prophet ability, in my experience.

Well, according to the Devs, the priests are smart enough not to cast fanaticism when it won't make any difference, which is before a unit has failed a morale check.