German Pietist and educationalist. He was already attracted to a pietistic form of religion when he came into contact with P. J. Spener. In 1691 he was appointed professor of Greek and Oriental languages at Halle and also pastor of Glaucha, near Halle. In 1696 he founded his ‘Paedagogium’ and his orphanage; both grew and a publishing house and dispensary were soon added. His theology was similar to that of Spener, but he placed more emphasis on the need for an inner religious struggle. The strict ethical code which he tried to impose gave his form of Pietism a legalistic turn which influenced the development of Pietism, especially in North and Central Germany.