Have you found any Christian advertising opportunities that are no cost or are low cost? I'd love to find some advertising for my business, but advertising isn't in the budget right now.
You'll need to be careful - check to make sure the directories use nofollow links, or that link could negatively impact your Search Engine Optimization. Google doesn't like link farms.
Another thing you can try is making a social media account for your website and following/commenting on fellow Christians' pages - that could stir up some traffic for you, and that is free.
Finally, do some keyword research and check on your Search Engine Optimization. Don't discount Google, Bing, etc, as traffic sources. If you need help for that, I recommend Search Engine Optimization for Dummies to help you optimize your sites for Google.