" The spiritual, political and economic situation in Europe was like a carefully built bonfire waiting to be lit, but the torch that set it burning was the spiritual crisis of Martin Luther. His struggle led eventually to the rediscovery of the doctrine of justification by faith. ... But what made the Reformation catch fire as an international movement of new life within the church was the reduplication of Luther's experience and insight among a number of Christian humanists who found this doctrine the key to their spiritual release and to their conceptual understanding of the needs in Western Christendom. "

― Richard F. Lovelace , Dynamics of Spiritual Life: An Evangelical Theology of Renewal