As important as the Greek magical papyri are to the understanding of Greco-Roman religion, as noted by Betz in his Introduction to the Greek magical texts, their full significance can be perceived only when it is realized that these texts written in Greek are part of a larger corpus that also includes texts written in that stage of the Egyptian language known as "Demotic," and that the corpus as a whole derives in very large measure from earlier Egyptian religious and magical beliefs and practices.