Religion is an important part of the daily lives of most of the characters in The Moonstone, as it was for most English people in the nineteenth century. But of course there are degrees: both Rachel and her mother, Lady Verinder, are Christian and members of the Church of England. But their relative, Miss Clack, is convinced that they're going to go to hell unless they convert to her branch of Christianity (an extremely evangelical form of Methodism). Godfrey Ablewhite is very vocal about his faith, as well. But both Ablewhite and Miss Clack are total hypocrites. In the world of The Moonstone, it seems that those who talk about their religion all the time are more likely to be hypocrites about it.
Characters in The Moonstone who flaunt their religious faith are the most likely to be hypocritical. Collins seems to condemn evangelism in favor of a more private morality.