This is a thorough study and exposition of the last work for which St Bonaventure was responsible before his death in 1274. The Collations on the Hexaemeron, also called The Illuminations of the Church comprises lectures that he gave in Paris in 1273 to Franciscan and other students and masters in the university there. They were recorded by two independent witnesses and one version, the definitive one, was prepared for publication and approved by Bonaventure. This is one of the most interesting, original and important texts of medieval theology and it has been well translated and edited in a new edition. The purpose of this study is to examine the precise context for the approach that Bonaventure took, to place this work as the culmination of his spiritual theology, and to provide the reader with a lucid epitome of the contents of the text, drawing out their significance for theology and prayer in the life of the Church today.