Kant's approach to faith is rational rather than simply faithful, which causes him to disdain the idea that one can obtain (or ought to seek) justification by faith alone. To look to God when you aren't shifting the load yourself strikes him as a doomed project, as you are unworthy of the help you seek.
He also brings the Stoics in for some criticism in thinking the natural inclinations are the primary evil in the hearts of men. Not so, he says: the natural inclinations are good, as long as they are well-managed.
Even just the first couple of pages here ought to make for an interesting and worthy discussion.