Last Updated September 5, 2023.
This is an analysis of The Journey of the Mind Into God by Saint Bonaventure, who was born Giovanni di Fidanza. It's not a recapitulation of the book's contents. If you want to know what's in it, read it or check out the excellent study guide on this website. The book is dense and difficult to read, but I highly recommend it.
The book is basically a road map for Christian conversion, addressed not to illiterate medieval heathens but to Church theologians and educated Europeans. The text's appeal to logic and reason at first seems unusual, but recall that mid-Thirteenth-Century Franciscan monks like Bonaventure were well-known empiricists. Roger Bacon is perhaps the most famous of these, and he was Bonaventure's contemporary; when he tries to persuade readers of the logic of conversion by appealing to nature and rationality, he's following the conventional wisdom of his order.
If you undertake the journey laid out in the book, you are led step-by-step through a six-part argument about Nature, about yourself, and about the essence of God. The outcome of this is supposed to be your acceptance of Jesus as your savior. The interesting part of this argument, one which is typical of medieval empiricist philosophy, is that your reason gets you all the way to God, "to the gate" as theologians put it then, but it doesn't get you "into God" or "through the gate." That's a leap of faith. You have to leave your reason behind. It's a neat juxtaposing of the practical faith traditions of the early and medieval Church with the inklings of a system of thought that brings Europe to the Enlightenment five hundred years after Bonaventure's book was published.
His argument was an attempt to accommodate competing pressures on Church doctrine: the need to give Christian theology some temporal intellectual clout and the wish to head off a doctrinal schism inside the Church. Feudalism and the absolute power of the Church in Europe were waning by the Thirteenth Century, and as the lords and bishops struggled to keep power they looked to philosophers, most of whom were in the Church then, for anchors on which to fasten their efforts.
As a work of theology and philosophy, Bonaventure's book can be read with Roger Bacon's work or that of Duns Scotus. There are echoes of it in Meister Eckhardt's work. Even the Twentieth Century priest, Dietrich Bonhoeffer, traces his ideas back to Bonaventure and his peers.