Ernst Troeltsch was a German Protestant theologian and writer on philosophy of religion and philosophy of history, and an influential figure in German thought before 1914, including as a member of the history of religions school. His work was a synthesis of a number of strands, drawing on Albrecht Ritschl, Max Weber's conception of sociology, and the Neo-Kantians of the Baden school.
His The Social Teachings of the Christian Church is a seminal work in this area.
While religious thinking in the days of the Weimar Republic moved away from his direction, Troeltsch's work in the sociology of religion remains important.
You have... the Gospel written upon vellum; it deserveth to be set with diamonds, except that the heart of man were a fitter repository for it. ... The Colloquies of Erasmus February 13, 1999 Faith is the source of energy in the struggle of life, but life still remains a battle which is continually renewed upon ever-new fronts. For every threatening abyss that is closed, another yawning gulf appears. The truth is -- and this is the conclusion of the whole matter -- the Kingdom of God is within us. But we must let our light shine before men in confident and untiring labor that they may see our good works and praise our Father in Heaven. The final ends of all humanity are hidden within His hands.