www.well.com/~davidu/mithras.html

The ancient Roman religion known as the Mithraic mysteries has captivated the imaginations of scholars for generations. There are two reasons for this fascination. First, like the other ancient "mystery religions," such as the Eleusinian mysteries and the mysteries of Isis, Mithraism maintained strict secrecy about its teachings and practices, revealing them only to initiates. As a result, reconstructing the beliefs of the Mithraic devotees has posed an enormously intriguing challenge to scholarly ingenuity. Second, Mithraism arose in the Mediterranean world at exactly the same time as did Christianity, and thus the study of the cult holds the promise of shedding vital light on the cultural dynamics that led to the rise of Christianity.