When I first opened his De Incarnatione I soon discovered I was reading a masterpiece ... for only a master mind could have written so deeply on a subject with such classical simplicity. -- C.S. Lewis, from the Introduction By any standard, this is a classic of Christian theology. Composed by St. Athanasius in the fourth century, it expounds with simplicity the theological vision defended at the councils of Nicaea and Constantinople: that the Son of God himself became "fully human, so that we might become god." Its influence on all Christian theology thereafter, East and West, ensures its place as one of the few "must read" books of Christian theology for all time. We are pleased to offer this new translation with a full introduction by C.S. Lewis. This book is also available from SVS Press with the original Greek text presented on the facing page.