In 1675 Spener published his great work, _Pia Desideria_. Here he laid down his platform: _That the word of God should be brought home to the popular heart; that laymen, when capable and pious, should act as preachers, thus becoming a valuable ally of the ministry; that deep love and practical piety are a necessity to every preacher; that kindness, moderation, and an effort to convince should be observed toward theological opponents; that great efforts should be made to have worthy and divinely-called young men properly instructed for the ministry; and that all preachers should urge upon the people the importance of faith and its fruits._ This book was the foundation of Spener's greatest influence and also of the strongest opposition with which he met. As long as he taught in private he escaped all general antagonism; but on the publication of his work he became the mark of envy, formalism, and high-churchism. After he was invited to Dresden in 1686, the state church indicated a decided disapprobation of his measures. He incurred the displeasure of the Elector by his fearless preaching and novel course of educating the young. His teaching of the masses drew upon him the charge that "a court-preacher was invited to Dresden, but behold, nothing but a school teacher!" He deemed it his duty to accept the invitation of Frederic of Brandenburg to make Berlin his residence, where, in 1705, he ended his days, after a life of remarkable usefulness but of unusual strife. It would be a pleasure to linger a while in the beautiful scenes which Spener's life affords us. Endowed with the most childlike nature, he was nevertheless a lion in contest. And yet who will find any bitterness in his words; where does he wax angry against his opponent? He did not shun controversy, because his mission demanded it; but no man loved peace more than Spener. His mind was always calm; and it was his lifelong aim to "do no sin." His enemies,--among whom we must not forget that he had a Schelwig, a Carpzov, an Alberti, and a whole Wittenberg Faculty,--never denied his amiable disposition; and it was one of his expressions in late life that "all the attacks of his enemies had never afflicted him with but one sleepless night." It was his personal character that went almost as far as his various writings to infuse practical piety into the church. He was respected by the great and good throughout the land. Crowned heads from distant parts of the Continent wrote to him, asking his advice on ecclesiastical questions. He was one of those men who, like Luther, Wesley, and others, was not blind to the great service of an extensive correspondence. He answered six hundred and twenty-two letters during one year, and at the end of that time there lay three hundred unanswered upon his table. His activity in composition knew no bounds. For many years of his life he was a member of the Consistory, and was engaged in its sessions from eight o'clock in