Denis the Carthusian

Denis the Carthusian (1402–1471), also called Denys van Leeuwen, was born at Rijkel in the territory of Liège, in present-day Belgium. After studying at Cologne he entered the charterhouse of Roermond in 1425, where he spent most of his life. In 1451 and 1452 he accompanied the papal legate Nicholas of Cusa on his mission of reform in Germany and the Low Countries, and from 1465 he directed a new Carthusian foundation at 's-Hertogenbosch.

He was among the most prolific writers of the Middle Ages. His works, which fill forty-two volumes in the modern edition, include commentaries on the whole of Scripture, on Peter Lombard's Sentences, on Boethius and on the writings of Dionysius the Areopagite, as well as treatises on contemplation and on the reform of the Church. He drew on the whole scholastic tradition, above all Thomas Aquinas, and combined it with the mystical theology of his own order; his ecstatic experiences of prayer earned him the title Doctor Ecstaticus.

The library holds his commentaries on the Song of Songs and on the Letter to the Ephesians, which show his method of reading Scripture literally and then spiritually.