It would be most erroneous to suppose that this controversy is either entirely or in the main directed against books and leaves, propositions and words. It looks rather to the soul and spirit, and seeks to drive away, to remove, and banish from them, and utterly to extirpate, all the deadly seeds of error and falsehood, replacing them by truth in all its fullness and energy, so as to win the minds and souls of men to its beneficent rule.
This, however, is only possible by an individual process and a personal interchange of ideas. For error and the restoration of truth assume a thousand different shapes, according to the different temperaments of individuals, or to the different periods of life in each. If, therefore, it be the wish or duty of philosophy to make this its principal aim, it is only in the form of dialogue that it can successfully accomplish the task, by suiting itself and closely conforming to the personal character of individuals. In this sense, and on this account, Plato, and the other disciples of Socrates, in their controversy with the Sophists, invariably employed the dialogical style, and chose this form for the exposition of their philosophical views. But even the written dialogue can not do more than exhibit, as it were, a vertical section of the whole infinite variety of individual views, convictions, and characters. And what thereupon is to be done in order to set them free and emancipate them from error, and to win them for, and to fill them with, the truth?
The inner sense for the truth and the spiritual eye must be opened, and the spirit of man must be led back and restored to its lost center. But the soul must be won and attracted, totally converted and endued with new life. But is this possible without some higher and divine power? Can it be accomplished by man's ordinary art of disputation, even though it be perhaps sufficient for the ordinary transactions of a civil tribunal; or by a logical train of proofs, or by the skillful terms of a well-managed dialogue, in the absence of all profounder power to move and actuate the soul?
And such a higher power and effectual word of truth does exist. In the language of Scripture it is called the Sword of the Spirit, which pierces to the very marrow and divides asunder the soul and the spirit. A deep meaning is involved in this expression of the dividing asunder of soul and spirit, and the very greatest of all the soul's pains is most appropriately indicated thereby. In death the immortal soul is separated and departs from the body; but soul and spirit still continue together in indissoluble union. These words, then, allude to some other and more violent separation. And it is one, moreover, which is indispensable to the triumph of truth in this struggle for life and death. For when error goes to the inmost depths, and reaches to the very center of life, both spirit and soul grow and adhere together, and the delusion can not otherwise be dispelled than by the violent separation of the two. And thus the light suddenly shines upon the spirit to show it the abyss on whose brink it stands, while the soul is simultaneously set free from all the chains which bind it to its false life, and is thereby completely changed and converted. In this way is the triumph of truth over error and infidelity effected. Only we must remember that the Sword of the Spirit, "which pierces even to the dividing asunder of soul and spirit, and of the joints and marrow," needs not always to be properly a spoken or a written "word." In some deeply-moving catastrophe of a man's life it makes a distinct and speaking manifestation of itself, working in him a total change of his feelings and sentiments. But the Spirit's flaming sword of judgment may be turned not only upon individuals, but also upon whole nations and ages, to divert them from error and unbelief, and to lead them back to truth. Lastly, it may also be directed toward the whole world and the whole human race; and to this interesting topic, which in so many ways is brought so immediately home to the present era of the world, we shall, in the course of the following Lectures, have occasion to recur.