In literary history, there may be no topic better covered than William Shakespeare. Harvard’s libraries hold well over 10,000 books on the great dramatist and his influences. Could there still be something about his work that we’ve missed?

Yes, says English scholar Daniel Swift. In his book “Shakespeare’s Common Prayers,” Swift argues that Shakespeare’s writing shows a deep and unappreciated reliance on The Book of Common Prayer, an immensely popular worship guide that collected prayers, Bible passages, and church rites into a strange and powerful text.