"The religious believer can make himself sure of his state of grace either in that he feels himself to be the vessel of the Holy Spirit or the tool of the divine will. In the former case his religious life tends to mysticism and emotionalism, in the latter to ascetic action; Luther stood close to the former type, Calvinism belonged definitely to the latter. The Calvinist also wanted to be saved sola fide. But since Calvin viewed all pure feelings and emotions, no matter how exalted they might seem to be, with suspicion, faith had to be proved by its objective results in order to provide a firm foundation for the certitudo salutis. It must be a fides efficax, the call to salvation an effectual calling (expression used in Savoy Declaration)."