I'm familiar with Domain Draughts but is there a permanent way to gain access to the Healing Domain when your deity does not grant it?
Mostly very limited options
There is one good option here, but everything else that can do this, can either only do it for very particular characters, can only kind of do it, or else probably can’t do it, but you can make a really weak argument for it if you squint.
But really, the real answer is that this isn't supposed to happen. Officially, a radiant servant of Pelor must worship Pelor—a deity who offers the Healing domain. Complete Divine does not contemplate radiant servants of Pelor who worship anyone else. Even a DM chooses to adapt the prestige class to allow that, they should adapt the abilities accordingly to match the domains of the actual deity being worshipped.
Heretic of the Faith—only option that definitely works
The Heretic of the Faith feat from Powers of Faerûn does many things including exactly what you want:
If you have access to domains, you can exchange any one domain you have with another domain outside those normally available to your faith. The new domain must be consistent with the tenets of your heresy (as adjudicated by the DM).
(Powers of Faerûn, pg. 46)
Note that this feat has a lot of fluff consequences, especially in the Forgotten Realms, and expects you to do some legwork defining your heresy. This is also a replacement, so take care with that. The Healing domain is not good, so giving up some other domain for it is a bad choice.
Customize Domain—Healing domain spell from another domain?
The Customize Domain feat from Dragon vol. 325 does this:
You permanently exchange spells on your domain spell list for similar spells on any spell list you have access to. […] adhere to the following restrictions by domain. […]
Good: Spells with the good descriptor.
Protection: Abjuration spells.
Strength: Spells that grant a bonus to Strength or cause a penalty to Strength.
Sun: Spells with the light descriptor.
(Dragon vol. 325, pg. 61)
The feat doesn’t describe what “similar spells” are for non-core domains, so whether Lathander’s non-core domains (Glory, Nobility, Renewal) will allow healing spells is up to the DM. Renewal feels like a reasonable bet, seeing as it already has several, though.
Anyway, assuming you are allowed to use Customize Domain to swap some spells on one of your domains for healing spells, and you choose some of the specific spells found on the Healing domain, you are then casting a “spell from the Healing domain” as a “domain spell.” That’s probably good enough to trigger radiant servant of Pelor’s empowered healing, maximized healing, and supreme healing.
Singer of concordance—Io only, but otherwise this just works
Singer of concordance is a prestige class from Races of the Dragon devoted to the draconic god Io. It offers this class feature:
Bonus Domain: At 2nd level, you gain access to an additional cleric domain from the following list of domains: Dragon, Healing, Knowledge, Magic, Strength, Travel, or Wealth. You gain the granted power associated with the domain you choose, and you can select the spells in that domain as your daily domain spells.
(Races of the Dragon, pg. 92)
Interestingly, these aren’t just Io’s domains—importantly for you, Healing isn’t otherwise available to clerics of Io. That means a cleric of Io—a deity that does not offer the Healing domain—can get the Healing domain with this prestige class. That makes this an answer to the question as stated—if, ya know, you can get in at all.
Singer of concordance requires the worship of Io—much like radiant servant of Pelor requires the worship of Pelor. If you were allowed to be a radiant servant without Pelor, maybe you can also be a singer of concordance without Io. If so, you can get Healing here too.
Requirements are otherwise pretty easy: Knowledge (religion) 8 ranks, 3rd-level divine spells, and the dragonblood subtype (which you can get from the Dragontouched feat if you don’t already have it). Advances spellcasting on all 10 levels.
Radiant servant of Pelor—Pelor only, but I guess that’s no problem
This is, in reality, not an answer: this does not officially allow someone who worships a deity without the Healing domain to get the Healing domain; officially, it only lets someone whose deity offers Healing to get it (as a third domain). On the other hand, radiant servant of Pelor is a prestige class from Complete Divine that you are, apparently, already taking, so I guess that it could work for you even though it doesn’t, officially.
Anyway, at 5th level you get this:
Bonus Domain: A radiant servant who reaches 5th level is granted another of Pelor’s domains as a third cleric domain, or he can choose the Glory or Purification domain. He can use the granted power of the new domain, and he can choose from the spell lists of three domains when selecting his domain spells for the day.
(Complete Divine, pg. 53)
Healing is one of “Pelor’s domains,” which is what this feature gives you. You aren’t a cleric of Pelor, so it would make sense to adapt this to your actual faith—but then, if you do that, it would also make sense to adapt empowered healing, maximized healing, and supreme healing to work with a domain you actually have. For a prestige class dedicated to a deity to have functionality that requires a domain that deity doesn’t offer makes no sense.
If for some reason, this bonus domain is adapted for your faith, but empowered healing, maximized healing, and supreme healing are not, you can combine this with Heretic of the Faith to effectively get Healing and both domains you would otherwise choose.
Domain staff—spells only
A domain staff from Complete Champion does this:
By expending a prepared divine spell or divine spell slot, the wielder can “cast” a spell of the same level or lower from the runestaff’s [sic] list, as long as that spell also appears on the wielder’s divine class spell list (including his domain lists, if any). Treat the domain spell as a spell of its level in the domain, even if it appears on your spell list at a different level. The spell is treated exactly as if the wielder cast the spell himself, including caster level, save DC, and any other effects related to the spell. Each spell can be cast from a domain staff once per day.
(Complete Champion, pg. 143)
They’re pretty expensive (36,000 gp), there are a lot of hoops to jump through (only spells on your spell list, each only once per day, you still need to use your actual spell slots, and you can only attune one domain staff at a time while refreshing your spells, so you can’t even buy multiple copies to get around the per-day restriction). But with a domain staff of healing, you can expend a domain spell to cast a spell from the Healing domain instead, “exactly as if [you] cast the spell [your]self.” Strictly speaking, it isn’t quite a domain spell in this instance (such as for radiant servant of Pelor’s empowered healing, maximized healing, or supreme healing abilities), but that is splitting some truly fine hairs, since it is in all but name.
Catalogues of Enlightenment—granted ability only
You can attune to the Catalogues of Enlightenment (Planar Handbook) with either the Touchstone feat (Sandstorm) or the Planar Touchstone feat (Planar Handbook). That grants you the granted power of any one domain—yours could be Healing. It isn’t technically permanent, but it lasts until you decide to attune to some other touchstone location, so if you never do that, it’s as good as permanent. You also don’t actually have to visit the Catalogues of Enlightenment yourself to get this effect. (You can get a temporary additional power by visiting but that is separate from the granted domain.)
This does not allow you to prepare Healing domain spells on domain spell slots—though since they’re all cleric spells anyway, that probably doesn’t matter. More important might be that you may not qualify for things that need the Healing domain per se, since you have only the granted ability. Since the Healing domain is generally pretty awful, that could be a deal-breaker as there may not be any other reason to get it. Talk to your DM, though—since you can cast all the spells in the domain, and you have its granted ability, that might be good enough for a given table/campaign.
Anyspell—spells only, from another domain you can’t get
The Spell domain from Spell Compendium includes anyspell and greater anyspell, and
Anyspell allows you to read and prepare any arcane spell of up to 2nd level. […]
[…] The prepared spell occupies your 3rd-level domain spell slot. […]
(Spell Compendium, pg. 15)
Thanks to the bard, you can get various spells from the Healing domain as arcane spells, which means you can prepare them in your domain slot with anyspell, which means you can cast them from a domain slot and qualify for maximize healing, empowered healing, and supreme healing.
Note that anyspell requires you to actually have a spellbook (or scrolls), and you also effectively “lose” a spell level in the conversion, so this is painful. It’s also exclusively found on a domain you have no more access to than you do Healing, so it really isn’t helpful to you.
Hospitaler—3.0e, ignoring errata, and replacing other domains
The hospitaler was originally printed in Defenders of the Faith with this ability:
Spells: A hospitaler casts spells as a cleric (see Table 3—6: The Cleric, page 30 of the Player’s Handbook) and has full access to the general cleric spell list. Hospitaler levels are added to cleric levels to determine spells per day and spell effects. In addition, the hospitaler chooses two of the following domains: Healing, Protection, War, the prestige domain Glory (if she channels positive energy) or the prestige domain Domination (if she channels negative energy). Access to other domains is lost. Like a cleric, a hospitaler may spontaneously cast cure or inflict spells.
(Defenders of the Faith, pg. 60)
This would—probably, I think—make the hospitaler a class with its own spellcasting, which mirrors cleric spellcasting but with its own progression (capped at 10th level and thus at 5th-level spells). To go along with this clone of cleric spellcasting, you would get two domains—but from a specific list that need not match your deity’s. Neat, if it didn’t kill the domains you already had.
Confusingly, immediately after the spells ability was another ability, spells per day, which instead says hospitaler advances your divine spellcasting from another class.¹ One could even argue that this means you get fresh cleric spellcasting and advancement of another divine spellcasting class, which could itself be cleric. Frankly, though, the spells ability just isn’t that clear and you could argue instead that it just staples “full access to the general cleric spell list” and the chosen domains to whatever other divine spellcasting you’ve got. Nothing about the class blocks druids, I guess.
Anyway, they errata’d this in the Sage Advice column for Dragon vol. 286. That’s far enough back that this was when Wizards of the Coast was doing Dragon themselves, and it says “This is official errata,” emphasis theirs, so I guess it’s legit? It does seem ridiculous to assume that everyone with Defenders of the Faith is going to have a Dragon subscription, but this is apparently how things went back then. (Player’s Handbook, Defenders of the Faith, and Psionic Handbook are the only books to receive errata this way.) Point is, the errata nixes the “spells” ability—including the domains—and enshrines the “spells per day” ability as the one true hospitaler feature. Doesn’t bother to actually fix the spells per day ability itself,¹ but well, does that really surprise you at this point?
But even that doesn’t really matter, because the hospitaler officially got updated to 3.5e in Complete Divine. That version also has only the spells per day ability (corrected, this time), and on top of that nerfs the class to uselessness (three lost spellcasting levels).
Anyway, point is, if you somehow convince your DM to allow you to use the 3.0e hospitaler, and to ignore the errata for it, and ignore the very glaring errors in it that prompted the errata, you can get the Healing domain, plus another one besides. And lose your other domains in the process. The only reason this is remotely helpful is you could—in theory—take a level of hospitaler, ditching any domains you have at the time, and then get other domains of your faith after that, such as from contemplative (Complete Divine), which gains a bonus domain from those normally available to your faith at 1st (and again at 6th, if you want to stick it out that long).
- Though it initially specifies “cleric,” we’ll ignore that seeing as it discusses not advancing “damage with the smite evil ability,” and later on says “she adds the level of hospitaler to the level of whatever other divine spellcasting class the character has,” which both contradict the original “cleric” specification, and the example character is a paladin.