[Some of this is repeated in a later post on reuniting spiritual theology with doctrinal theology.]
In the Middle Ages theologians began to separate doctrinal theology from spiritual theology (ie practice) or perhaps just neglect spiritual theology. This makes theology boring. Before then theology and practice were integrated. Classic works that integrated spiritual theology with doctrine include Augustine’s On the Trinity in the 5th century and Bernard of Clairvaux’s Commentary on the Song of Songs in the early 12th century. After Bernard theology became focused on greater systemization of doctrine, and spiritual theology (or sanctification as the Reformers came to call it) received less attention in theological systems.
The classic example of greater systemization is Thomas Aquinas Summa Theologica, written near the end of the 13th century which became the dominant theology in the Roman Catholic Church. The Summa contains helpful teachings on practice of the faith but it is dominated by detailed intellectual analysis of doctrine. Aquinas does discuss spiritual growth, but it was much less emphasized than in previous centuries. Perhaps this was due to medieval scholasticism and the growing influence of Aristotle’s amazing systemization of philosophy. It may also be due to the general human tendency to dwell on the intellectual since that is easier than focusing on how we need to change. At any rate, spiritual theology, or practice, was becoming mostly separate from doctrinal theology.
The doctrines related to practice of the faith, i.e. Spiritual theology, came to be dominated by radical followers of Jesus such as the Franciscans and the Brethren of the Common Life. Other religious orders as well as mystics also emphasized practice. Christian teaching became split between the teachers of truth and the practitioners of the faith. The Imitation of Christ by Thomas a Kempis is a premier example of spiritual theology produced by religious orders. (Spiritual theology without a lot of explicit theology doesn’t seem to be intrinsically bad, probably because it always has some explicit and implicit doctrine. The problem comes when the situation is reversed)
With the Reformation theology became almost exclusively about “what is” instead of “how do we grow and live”, i.e. it became focused on doctrine rather than practice. This was probably because the Reformers wanted to thoroughly address the great doctrinal abuses of the roman church and provide a coherent alternative. The theologies of the Reformers had very short discussions of sanctification.
Thus, doctrine and practice became separated, and that is why theology often seems dry. Without integration of living the Christian life it seems boring.
