Every time my group starts a new campaign or adventure with new characters, the caveat is that they must try and play something new and different. None of them have played a cleric, ever.
The Problem: Worship and Theism
I have tried to tempt the players into the Cleric role: amazing spell list, very versatile play styles, could be great fun roleplaying (basically built in to character creation)! No bites. They even know that they won't be heal bots, they can get creative!
I feel that the piety aspect is what is holding them all back. Organized religion is something that they seem too cower away from. This stems from the fact, or the apparent fact that, despite the option allowing Clerics to follow an "ideal" instead, the PHB and errata seems to still direct a Cleric to choose a deity (emphasis mine):
While the vast majority of clerics revere a specific deity, a small number dedicate themselves to a divine concept worthy of devotion—such as battle, death, justice, or knowledge—free of a deific abstraction. (Work with your GM if you prefer this path to selecting a specific deity.)
Which, to me, translates into a Cleric needing to pick a specific deity.
Clerics who follow a philosophy must select a patron deity among the
philosophy’s associated religions (they gain no additional benefits
from adherence to a philosophy). -Inner Sea World Guide
Even clerics, who must choose one deity as their patron above all
others, sometimes offer such minor prayers to divinities allied with
their chosen gods, although their faith must still remain primarily
focused on their deity of choice, for even the good gods can be
jealous. -Inner Sea Gods
A follower of a specific pantheon may take the Pantheistic Blessing
feat to gain access to a spell-like ability tied thematically to his
or her chosen pantheon. Note that single-class clerics gain their
powers through allegiance to a single deity, and therefore cannot
select this feat. -Faiths and Philosophies
And, while not a handbook, here is one of Creative Director James Jacobs' innumerable direct statements on the matter:
The official stance in Golarion is that if you're a cleric, you MUST
have a patron deity. That's one of the big things that makes clerics
not a different type of spellcaster.
(And yes, I wish I had a time machine so I could go back and fix the
Core Rulebook so that it says that there in the Core Rulebook as
You're free to say clerics don't need deities in games you run, just
as you're free to say wizards don't need spellbooks or rogues don't
need thieves' tools or whatever… but the baseline assumption for our
campaign setting is that clerics must worship a deity.
So, having established that a deity-less Cleric isn't really viable in our play setting: How can I encourage the players to give the Cleric a try without DM intervening and allowing a deity-less Cleric? And further to that, how can I help them roleplay the cleric so that it is fun and engaging?
Eventually, I suppose, once all other options have been exhausted, I'll have an entire party of clerics! 🙂
Make clerics interesting!
There are multiple ways of doing that. The first is to actually play a cleric, they are amazing, they are one of the strongest classes in the game and the most versatile after druids and wizards (Personally, I consider clerics more versatile than wizards, but that's me). I also had strong (bad) opinions on clerics, but then I played a few of them. And damn, what a blast I had, they are extremely fun and you can explore all sort of weird concepts with them, other than your typical healbot or cleric-necromancer.
The second is to introduce them to interesting deities, one at a time. If you find a certain god to be interesting, then maybe they will do too, but without reading about them, how will they know about it?
For instance, did you know the priests (and inquisitors) of Asmodeus (a lawful evil deity) are allowed to act as judges when there is no appointed judge for that city? Not only that, but you can roleplay characters with characteristics like of the Judge Dredd comic (and movie) character, and that is fine, because your word is the law (quite literally sometimes)!
Another example, churches of Abadar are banks! I kid you not, all of their temples are some sort of financial institute. They control the coinage, exchange rates and will give you credit to start your own business for a small fee if you prove that you are capable of doing it. I GMed a game where the players had to constantly deal with clerics of Abadar and one of them was converted to the faith so he could safely exchange trade goods with no risk of being called a cheater, as he had a badge (holy symbol) to prove that he was a reliable source of monetary information and knowledge.
Did you know that temples of Calistria are brothels, inns, and such? So, the next time the PCs wish to get some company, introduce them to the priestess of Calistria, and explain how their donations are being put to a good cause, like saving orphans from a war on a nearby country.
In another game, the church of Pharasma was so well connected to the PCs, both because they did many quests to help the church and because they donated a lot of recovered lost relics (cough archeologically stolen artifacts), that the church would cast any divine spells that they required, and that had a total material cost of 100 gp or less, for free! They used this to cast a bunch of divinations to guide themselves to their goal in that campaign. One of the players even talked to Pharasma herself (when he died, of course) because of this connection.
In that same campaign, they were saved by a monk/cleric of Irori, who defended them against a small horde of ghouls so they could escape safely. Being immune to diseases, he couldn't be affected by the ghoul's paralysis, and being a little higher level than the PCs, he displayed some awesome kung fu action in front of them by taking down single-handledly 12 ghouls and coming back later to tell the story. They had to escape before the combat was over, as 2 PCs were unconscious and paralyzed already. This NPC later became a valuable source of information (Irori is a god of knowledge after all) and allowed them to retrain most feats (a house rule, of course, but Irori is also a god of inner strength) when necessary. They loved Irori ever since.
One last example, in a campaign set in Osirion (which is an Egyptian-themed region), one player wanted to be a cleric of Sobek (the crocodile god) because of the domains associated with him (strength and war), but since we had so little information about that god in the setting and the choice of domains were pretty much for their crunch alone, the god was uninspiring to him once he had finished it. We sat down and looked up everything we could about the (real) god in the (real) Egyptian mythology. And we found out that he also had a strong association with blood (because the Egyptian believed that blood and water were connected) and we pretty much rebuilt the god around the whole "god of strength, water and blood sacrifices".
The result was epic, his Divinations used a crocodile heart as reagents (a flavor created by us), and every blessing involved dripping some blood on his teammates (mostly his own) while chanting some battle cry, while all of his curses involved either turning his own blood into a magical effect, or that of his enemies. Yeah, you read that right, it was all like the Kali-Ma priest from Indiana Jones. He would put his hand on a wound and splash it on his face before casting a Cure Wounds spell while chanting something like "Sobek accepts your sacrifice!" or "Your blood is not worthy!" before a Flame Strike.
As GM, ever since I got my hands in the Inner Sea Gods, I try to introduce a reliable NPC that can instill the awesomeness of their god to the PCs, like those examples above, on every campaign. Those NPCs don't have to be higher level, they just have to do something cool or useful to the party, even if that is simply being a barkeeper that worships Cayden and can turn water into beer for free to the PCs.
All of these examples applies to Golarion, but the spirit in my words go for any campaign setting of your liking. Read up about the gods in that setting, see what makes them interesting other than their powers and spheres of influence, what other gods are their allies or enemies, it's the little details that make them memorable. If your players can identify themselves and feel conneceted to those gods, they may consider worshipping them the next time you guys create new characters.