There are a couple of interesting posts on the Christian origins of Wiccan rituals over at Pantheon. See Is Wicca a Christian Heresy? and The Watchtowers and Abrahamic Wicca. I’m glad this is coming from a member of the Pagan community. It echos my own surprise upon first reading the earlier Golden Dawn rituals, on how Christian they sounded in comparison to later forms of Paganism.