Readable

In the comments to "Symptomatic," Marya asks, "which of your religious novels are actually fun, quirky reads, as opposed to slogs?"

"Fun" and "quirky" aren't usually the adjectives that come to mind when my religious novels are involved, but some of the authors are perfectly readable.  A few suggestions, in alphabetical order:

• Grace Aguilar.  Not a brilliant prose stylist, but her plotting and characterization are OK, and it's interesting to see a Jewish novelist trying to grab both the Protestant and the Jewish readerships at the same time.  Michael Galchinsky's recent anthology is a useful place to start.
• Elizabeth Rundle Charles.  Specializes in fictional diaries, frequently with multiple narrators; her representations of spiritual experience are often genuinely moving, and the characters are more nuanced and three-dimensional than the usual.  The best-known novels are in a series that begins with the enormously popular Chronicles of the Schonberg-Cotta Family.
• Dinah Mulock Craik.  Not as theological as the others on this list; creates some complex characters and reasonably sophisticated plots.  John Halifax, Gentleman is the novel everybody knows, but Olive is also interesting, as is A Life for a Life (which I praised with faint damns some time ago). 
• Charles Kingsley.  Kingsley's anti-Catholicism deserves the adjective "squicky" (he's far more overtly obsessed with sex than most of his contemporaries), but it's still the case that the novels themselves feature solid plotting and good dialogue.  (Granted, I have the urge to do violence to Alton Locke.) Alton Locke, Westward Ho! and The Water-Babies are the ones that have survived into the twenty-first century, but there's also Hypatia.
• Eliza Lynn Linton.  An evangelical agnostic, Linton tends to be amusingly (or at least assertively) grouchy (although her antifeminism can make modern readers similarly grouchy...). For Linton in full whack-the-church mode, try The True History of Joshua Davidson.   The Rebel of the Family, which I've not yet read, is in print.  (Do skip The Autobiography of Christopher Kirkland, unless you're very interested in Victorian name-dropping.)
• Anne Manning.  I think "amiable" is probably the best way of describing her style, but she's still perfectly tolerable and not always aggravatingly didactic.  She's also responsible for popularizing the diary novel.  (Brownie points for the "My Last Duchess" joke in Tasso and Leonora.)  Try The Maiden and Married Life of Mary Powell, Afterwards Mrs. Milton or The Household of Sir Thomas More.
• John Henry Newman.  Well, obviously, he's not primarily a novelist, and Callista--recently blogged at Siris--is not going to be for everybody; Loss and Gain, however, still goes over well (and features some amusing Victorian snark; Newman, unlike some religious novelists I can think of, actually was in the verifiable possession of a sense of humor.) 
• Charlotte Yonge.  Of the authors who tend to cross my research path, Yonge and Kingsley are the most famous today.  Start with the Heir of Redclyffe, which is still what they call a "good read."

Comments

[Brandon]

This is a great list to have; I've only read a small handful of the works you list, so they're going on my reading list.

I agree with the comment on Newman; I think most people would be interested in Callista only to the extent that they are interested in Newman's ideas generally, although it has its moments. Loss and Gain's humor, on the other hand, has worn very well.

IMO, Edwin Abbott Abbott has some nice religious novels -- Onesimus, for instance. Very didactic, but, since he manages to avoid direct preaching, enjoyable (although, since I'm a big fan of didactic anything, my tastes here are perhaps not to be trusted). If we are willing to count things that are really quirky, his Flatland probably could be considered a sort of religious novel (he seems to treat it as such on occasion, anyway, and it certainly engages in some religious satire). And fun and quirky is the order of the day there, since it manages to be a readable novel in which all the characters are geometrical shapes.

[Marya]

That is splendid, thanks! I will run, not walk, to my library's ILL desk.

[Arnold]

What a great list -- some I've already read and enjoyed, others I don't know and look forward to reading. I absolutely agree about Loss and Gain, one of my very favourite novels (and fascinating as a piece of social history, as well as being very amusing).

I have my own personal favourites, but most of them belong to the 'so bad it's good' category (like Charles Maurice Davies's deeply bizarre novel Broad Church). The only novel I'd seriously suggest adding to Miriam's list would be J.H. Shorthouse's John Inglesant, which is maybe a bit mannered but wins the reader over (or won me over, anyway) by its obvious sincerity.

[Ianthe]

I am myself a great Charlotte Yonge fan. Just speaking for myself, I think I'd start with _The Daisy Chain_ rather than _Redclyffe_. It's a tremendously interesting portrayal of an interesting family, and it could get you started on the "linked" novels (Yonge wrote a long series of novels with recurring characters who grow up, marry, have children, grow old)--which would give you a more-or-less permanent list of things to read.