Slushpile reader is a rip off. Sorry. My friend Ann Crispin, a fantasy and science fiction writer, has discussed this on her writers beware blog.
If you want publication by a traditional house, you have two approaches. Find a literary agent who handles "Christian" material. There are a number of good agent lists out there, both in print and on the internet. Do not expect the first agent to whom you submit to say yes. They will read the first few paragraphs. Within the first sentence or two they will assess your writing ability. It's a brutal world. Be prepared for rejections. My first book was rejected nearly 20 times before it found a publisher. It's often worse than that. The second approach is to find a "Christian" publishing house or any publisher who may look for that kind of material and submit to them directly. Read their submission guidelines. Check them out on Predators and Editors. There are many, many fraudulent publishers.
Your manuscript must be the best you can make it, brutally edited, clean. It should be your very best. Before you submit to anyone, have someone you trust for their critical ability and grasp of good writing read it and critique it. Join a critique group if you need to. My beta reader is a Canadian English professor. She's sharp and willing to put in the effort.
Commercial publishers look for things that will sell. No matter how good your prose may be, if they do not think it will sell and sell well, they will tell you no.
You can always publish on lulu.com. It's free to you. They offer "packages" for edits and such. Those cost money. If you're confident that you're all ready to go, you do not need them and can publish for free. Their profit comes from selling your book. They take a percentage. Lulu is great for limited interest and academic material that will see small circulation.
Visit Agent's blogs. Get a feel for what is demanded of you as a writer. It's an exceptional book that sees publication. Typically my agent gets 500-1000 queries in a month. An assistant wades through them first, pruning out the really awful. Out of that 'slush pile' she may request a "partial" from two individuals, sometimes three. A partial is the first few chapters of your manuscript. (Some agents ask for the first three chapters with your initial submission). She will either ask for the entire manuscript or tell you no.
Do not complain about rejections, and by all means do not say nasty things about publishers, editors, or agents. It's a very small world. Everyone talks to everyone else. You post something nasty or complain loudly about someone in the industry, others will hear it. Bad idea. Grit your teeth.
Those are your options.