Much of the material was collected by Barrett from older occult handbooks, as he hints in the preface: We have collected out of the works of the most famous magicians, such as
Zoroaster,
Hermes,
Apollonius, Simon of the Temple,
Trithemius,
Agrippa,
Porta (the Neapolitan),
Dee,
Paracelsus,
Roger Bacon, and a great many others... In fact, most of the material comes from Agrippa's
Three Books of Occult Philosophy and
Pietro d'Abano's
Heptameron. Previous
demonologists such as Binsfeld (1589) had drawn up lists that comprised a hierarchy of devils, and attributed to them the power to instigate people to commit the
seven deadly sins.
Lucifer was associated with
Pride,
Satan with
Anger and so forth. In
The Magus Barrett altered the "roster of devils" and Satan now became a prince of deluders (serving
conjurers and
witches). ==Publication and influence==