This classic work, first published in 1675, inaugurated the movement in Germany called Pietism. In it a young pastor, born and raised during the devastating Thirty Years War, voiced a plea for reform of the church which made the author and his proposals famous.
A lifelong friend of the philosopher Leibnitz, Spener was an important influence in the life of the next leader of German Pietism, August Herman Francke. He was also a sponsor at the baptism of Nicholas Zinzendorf, founder of the Moravian Church, whose members played a crucial role in the life of John Wesley.