From the publisher's website:
God is the patron of the Jewish people, his chosen people, guiding them through history and ultimately back to the Promised Land.
God is three and one, incarnate in Christ His Son, and offers salvation to all equally.
God is pure unity, with no parents or children, saving all who submit to His Will.
God is beyond human understanding, and all the above statements are true.
But the Divine Realm is not completely beyond human comprehension, and this book explains the power of God in Mythic Europe. From descriptions of each of the three great Divine religions, Judaism, Christianity, and Islam, to rules for Divinely-empowered wonder workers and angels, this book contains everything needed to include the Divine in your Ars Magica saga