Angelus Silesius (c. 1624 – 9 July 1677), born Johann Scheffler and also known as Johann Angelus Silesius, was a German Catholic priest and physician, known as a mystic and religious poet. Born and raised a Lutheran, he adopted the name Angelus (Latin for "angel" or "heavenly messenger") and the epithet Silesius ("Silesian") on converting to Catholicism in 1653. While studying in the Netherlands, he began to read the works of medieval mystics and became acquainted with the works of the German mystic Jacob Böhme through Böhme's friend, Abraham von Franckenberg. Silesius's mystical beliefs caused tension between him and Lutheran authorities and led to his eventual conversion to Catholicism. He took holy orders under the Franciscans and was ordained a priest in 1661. Ten years later, in 1671, he retired to a Jesuit house where he remained for the rest of his life.
