As a merely verbal matter, this identification of the Spiritual World with what are known to Science as Kingdoms, necessitates an explanation. The suggested relation of the Kingdom of Christ to the Mineral and Animal Kingdoms does not, of course, depend upon the accident that the Spiritual World is named in the sacred writings by the same word. This certainly lends an appearance of fancy to the generalization; and one feels tempted at first to dismiss it with a smile. But, in truth, it is no mere play on the word _Kingdom_. Science demands the classification of every organism. And here is an organism of a unique kind, a living energetic spirit, a new creature which, by an act of generation, has been begotten of God. Starting from the point that the spiritual life is to be studied biologically, we must at once proceed, as the first step in the scientific examination of this organism, to enter it in its appropriate class. Now two Kingdoms, at the present time, are known to Science--the Inorganic and the Organic. It does not belong to the Inorganic Kingdom, because it lives. It does not belong to the Organic Kingdom, because it is endowed with a kind of Life infinitely removed from either the vegetal or animal. Where then shall it be classed? We are left without an alternative. There being no Kingdom known to Science which can contain it, we must construct one. Or rather we must include in the programme of Science a Kingdom already constructed but the place of which in science has not yet been recognized. That Kingdom is the _Kingdom of God_.
Taking now this larger view of the content of science, we may leave the case of the individual and pass on to outline the scheme of nature as a whole. The general conception will be as follows:
First, we find at the bottom of everything the Mineral or Inorganic Kingdom. Its characteristics are, first, that so far as the sphere above it is concerned it is dead; second, that although dead it furnishes the physical basis of life to the Kingdom next in order. It is thus absolutely essential to the Kingdom above it. And the more minutely the detailed structure and ordering of the whole fabric are investigated it becomes increasingly apparent that the Inorganic Kingdom is the preparation for, and the prophecy of, the Organic.
Second, we come to the world next in order, the world containing plant, and animal, and man, the Organic Kingdom. Its characteristics are, first, that so far as the sphere above it is concerned it is dead; and, second, although dead it supplies in turn the basis of life to the Kingdom next in order. And the more minutely the detailed structure and ordering of the whole fabric are investigated, it is obvious, in turn, that the Organic Kingdom is the preparation for, and the prophecy of the Spiritual.
Third, and highest, we reach the Spiritual Kingdom, or the Kingdom of Heaven. What its characteristics are, relatively to any hypothetical higher Kingdom, necessarily remain unknown. That the Spiritual, in turn, may be the preparation for, and the prophecy of, something still higher is not impossible. But the very conception of a Fourth Kingdom transcends us, and if it exists, the Spiritual organism, by the analogy, must remain at present wholly dead to it.
The warrant for adding this Third Kingdom consists, as just stated, in the fact that there are organisms which from their peculiar origin, nature, and destiny cannot be fitly entered in either of the two Kingdoms now known to science. The Second Kingdom is proclaimed by the advent upon the stage of the First, of _once-born_ organisms. The Third is ushered in by the appearance, among these once-born organisms, of forms of life which have been born again--_twice-born_ organisms. The classification, therefore, is based, from the scientific side on certain facts of embryology and on the Law of Biogenesis; and from the theological side on certain facts of experience and on the doctrine of Regeneration. To those who hold either to Biogenesis or to Regeneration, there is no escape from a Third Kingdom.[98]