every address to the people this must be made the principal point--so to explain the text of Scripture that men may understand what the Holy Spirit chiefly and primarily intends to teach by it. Inasmuch, too, as the language is addressed to the people, it is the part of prudence to decide what words may suit their capacity. We should strive to state the fact on the doctrine itself in words as fitting and simple as possible, and (omitting all controversial subtleties) to prove the truth as far as it is necessary for salvation to be known, by a few words of Scripture:--few, that they may not escape the memory of the hearers; evident and convincing, lest the proofs seem doubtful, and the minds of the more intelligent be left in suspense and be disturbed to their very exceeding harm. The words of the Fathers (if used by way of evidence) should be used sparingly and with caution; lest the ignorant should confound the Apostles and Prophets with the Fathers, and persuade themselves that all have equal authority. For it is to be borne in mind that sermons are preached not so much for the benefit of the learned as for the sake of the people generally; that they may be rightly instructed in the doctrine of salvation and of Christian morals. In the meantime we must do our best to satisfy _all_; that the simple be not left without needful teaching; the more acute find no want of force and argument; nor the learned charge the preacher with a pride of knowledge foreign to the occasion and not always thorough."[13] In his first controversial work, _Chief Points of the Christian Religion_, Calixtus gave expression to many solid thoughts, which subsequently produced an abundant harvest. His _Theological Apparatus_ was written for young ministers, and designed to meet the immediate necessities of the times. But it is to his great work, the _Desire and Effort for Ecclesiastical Concord_, that we must turn to find the true man spending his greatest power toward the unification of Christians. In terms of communion, he contends, we must distinguish between what is, and what is not, essential to salvation. In all that relates to the Christian mysteries we must content ourselves with the _quod_ and not dispute about the _quo modo_. In stating these mysteries we should use the simplest language. There is a natural brotherhood of men, and this should bind them together in matters of religion. We must love all men, even idolaters, in order to save them. The Jews and Mohammedans stand nearer to us than they, and we should cherish affection also for them. Those who are most closely united to us are all who believe that they can be saved only by the merits of Christ. All who thus recognize the saving power of Christ are members of his body, brothers and sisters with him. We should live, therefore, as members of one family, though adhering to different sects.