I think he means Hierophant - as in the original one in the DMG.
I think this PrC - as most PrCs should be but no longer are - are really dependant upon the campaign and the character. Each of the Heirophant's special abilities could make them absolutely rock - or be pointless ... depending on the situation. For example.
Blast Infidel - A party made of of mostly LGs (paladins, clerics, etc) who intentionally go out and get hired to hunt down people that are most likely CEs could make really good use of the Blast Infidel special ability. But in a party that takes up any old assignment, this special ability may work part of the time but really isn't going to make you shine.
Divine Reach - This ability could be nice for healing or high dex characters as stated above. But it might be useless for a cleric who has low dex and refuses to be the party healer anyway!
Gift of the Divine - When playing with other high CHA characters, this ability really lets the heirophant let CHA be a dump stat. Want to successfully turn wth a low CHA character ... just hand it over to the others who can do more with it anyway.
Mastery of Energy - Incredibly useful in a party of Undead Hunters ... but if the party doesn't fight many undead this will be useless, really.
Metamagic Feat - Not a big gain or loss ... just a general application of a specific ability.
... and so on and so forth. This is the way I think all PrCs should be. Really great for specific adventures but not desirable for others.