Devotio Moderna

Geert Groote was a well-connected and comfortably provided cleric of Deventer who, in the mid 1370s, gave that up after an illness and a period with the Carthusians. He took deacon's orders, obtained a licence to preach in the diocese of Utrecht, and preached against clerical concubinage and simony to very large audiences until the licence was withdrawn. He gave over part of his own house in Deventer to a group of devout women living in common, and after his death in 1384 his followers organised themselves as the Brethren and the Sisters of the Common Life.

The arrangement was the point and the problem. They lived together, pooled their earnings, obeyed a rector and kept a rule of life, but they took no vows, wore no habit and were free to leave, which meant they were not a religious order and could not be governed as one. That drew repeated accusations of running an illicit order under another name, and the houses had to defend their legal position more than once.

The Windesheim congregation, founded in 1387 as a house of Augustinian canons regular, was in part the answer to that: an unambiguously canonical form for those who wanted one, which grew into a large congregation of monasteries and carried the movement's spirit inside conventional structures.

The Brethren supported themselves by copying manuscripts, and the choice was not only economic. Copying put devotional texts into circulation, occupied the hands while the mind attended to what was being written, and gave houses a product that towns wanted. Several houses moved into printing when printing arrived.

Their characteristic private instrument was the rapiarium, a personal notebook into which a reader copied passages that had struck him, rearranged them, and returned to them. The devotional method that goes with it is slow, repetitive and interior: short passages, taken deliberately, applied to one's own conduct, with a suspicion of speculative theology that runs through the whole movement.

The Imitation of Christ, attributed to Thomas a Kempis, a canon of the Windesheim house of Mount St Agnes, is a rapiarium turned into a book, and it became the most widely circulated Christian devotional work after the Bible. The Brethren also taught, or lodged and supervised, schoolboys in Deventer, Zwolle and elsewhere, and Erasmus was among those schooled in that orbit.

How far the movement prepared the ground for the Reformation is an old argument and not a settled one. John Van Engen's account resists the older reading of it as a proto-Protestant current, presenting it instead as a late medieval experiment in devout life that stayed inside the church it reformed.