The oneness of the dispensations has been proved. They are one in their design, in their threatenings, in their promises. If we seek the fundamental ground of this threefold unity, we shall find it in the fact that both dispensations are parts of a Divine revelation. God has spoken, and the word of God does not pass away. “Think not,” said our Lord, “that I came to destroy the Law or the prophets; I came not to destroy, but to fulfil. For verily I say unto you, Till heaven and earth pass away, one jot or one tittle shall in no wise pass away from the Law till all things be accomplished.”[54] On another occasion He says, “Heaven and earth shall pass away, but My words shall not pass away.”[55] These passages teach us that the words of God through Moses and in the Son are equally immutable. Many features of the old covenant may be transient; but, if it is a word of God, it abides in its essential nature through all changes. For “the word of God is living,”[56] because He Who speaks the word is the living God. It acts with mighty energy,[57] like the silent laws of nature, which destroy or save alive according as men obey or disobey them. It cuts like a sword whetted on each side of the blade, piercing through to the place where the natural life of the soul divides[58] from, or passes into, the supernatural life of the spirit. For it is revelation that has made known to man his possession of the spiritual faculty. The word “spirit” is used by heathen writers. But in their books it means only the air we breathe. The very conception of the spiritual is enshrined in the bosom of God’s word. Revelation has separated between the life of heathenism and the life of the Church, between the natural man and the spiritual, between the darkness that comprehended it not and the children of the light who received it and thus became children of God. Further, the word of God pierces to the joints that connect the natural and the supernatural.[59] It does not ignore the former. On the contrary, it addresses itself to man’s reason and conscience, in order to erect the supernatural upon nature. Where reason stops short, the word of God appeals to the supernatural faculty of faith; and when conscience grows blunt, the word makes conscience, like itself, sharper than any two-edged sword. Once more, the word of God pierces to the marrow.[60] It reveals to man the innermost meaning of his own nature and of the supernatural planted within him. The truest morality and the highest spirituality are both the direct product of God’s revelation.