"Progress of his Version. Luther was gradually prepared for this work. He found for the first time a complete copy of the Latin Bible in the University Library at Erfurt, to his great delight, and made it his chief study. He derived from it his theology and spiritual nourishment; he lectured and preached on it as professor at Wittenberg day after day. He acquired the knowledge of the original languages for the purpose of its better understanding. He liked to call himself a "Doctor of the Sacred Scriptures.""