4. The terms expanse and heaven, previously applied to the atmosphere, are here combined to denote the more distant starry and planetary heavens. There is no ambiguity involved in this, since the writer must have well known that no one could so far mistake as to suppose that the heavenly bodies are placed in that atmospheric expanse which supports the clouds.
5. The luminaries were made or appointed to their office on the fourth day. They are not said to have been created, being included in the creation of the beginning. They were now completed, and fully fitted for their work. An important part of this fitting seems to have been the setting or placing them in the heavens, conveying to us the impression that the mutual relations and regular motions of the heavenly bodies were now for the first time perfected.
6. The stars are introduced in a parenthetical manner, which leaves it doubtful whether we are merely informed in general terms that they are works of God, as well as those heavenly bodies which are of more importance to us, or that they were arranged as heavenly luminaries useful to our earth on the fourth day. The term includes the fixed stars, and it is by no means probable that these were in any way affected by the work referred to the fourth day, any farther than their appearance from our earth is concerned. This view is confirmed by the language of the 104th Psalm, which in this part of the work mentions the sun and moon alone, without the fixed stars or planets.
It is evident that the changes referred to this period related to the whole solar system, and resulted in the completion of that system in the form which it now bears, or at least in the final adjustment of the motions and relations of the earth; and we have reason to believe that the condensation of the luminous envelope around the sun was one of the most important of these changes. On the hypothesis of La Place, already referred to as most in accordance with the earlier stages of the work, there seems to be no especial reason why the completion of the process of elaboration of the sun and planets should be accelerated at this particular stage. We can easily understand, however, that those closing steps which brought the solar system into a state of permanent and final equilibrium would form a marked epoch in the work; and we can also understand that now, on the eve of the introduction of animal life, there is a certain propriety in the representation of the Creator interfering to close up the merely inorganic part of his great work, and bring this department at least to its final perfection. The fourth day, then, in geological language, marks the complete introduction of "existing causes" in inorganic nature, and we henceforth find no more creative interference, except in the domain of organization. This accords admirably with the deductions of modern geology, and especially with that great principle so well expounded by Sir Charles Lyell, and which forms the true basis of modern geological reasonings—that we should seek in existing causes of change for the explanation of the appearances of the rocks of the earth's crust. Geology probably carries us back to the introduction of animal life; and shows us that since that time land, sea, and atmosphere, summer and winter, day and night—all the great inorganic conditions affecting animal life—have existed as at present, and have been subject to modifications the same in kind with those which they now experience, though perhaps different in degree. In this ancient record we find in like manner that the period immediately preceding the creation of animals witnessed the completion of all the great general arrangements on which these phenomena depend. The Bible, therefore, and science agree in the truth that existing causes have been in full force since the creation of animals; and that since that period the exercise of creative power has been limited to the organic world. This has a curious bearing, not often thought of, on modern theories of evolution as compared with the teaching of the Bible. In one important sense, absolute creation, in so far as the inorganic universe is concerned, is in our Mosaic narrative limited to the production of matter and force at first. All else is called making, forming, or appointing. Thus the production of all the arrangements of the waters, the atmosphere, the earth, and the heavens, in the work of the first four days, and even the introduction of plants, may be correctly termed an evolution or development from preformed materials, with the single exception that the reproductive power and specific diversities of plants are recognized as entirely new facts. Creation is properly resumed when animal life is introduced. Hence, in so far as a comparison with the terms of Genesis is concerned, hypotheses as to the evolution of animal life from inorganic matter are in a different position from hypotheses as to the previous evolution of the parts of inorganic nature; and still more so from statements as to the progress of inorganic nature subsequent to the introduction of animals; since within that period, which really includes the whole of geological time, absolutely no creation whatever in the domain of inanimate nature is affirmed in the Biblical record to have taken place. On the contrary, all the arrangements of inorganic nature are represented as finally completed before the creation of animals.
The obliquity of the earth's axis, which gives us the changes of the seasons, is apparently included in the arrangements of the fourth creative day. The cause of this obliquity, and the time when it may have attained to its present amount, have been fertile themes of discussion. It is clear, however, that if this obliquity was established, as appears to be stated here, before the introduction of animal life, it can have no bearing on the changes of climate of which we have evidence in geological time since the dawn of animal life, unless, indeed, it is capable of greater variation than astronomers admit; and the same remark applies to supposed changes in the position of the poles themselves. There is, however, nothing in this record to oppose the idea of any secular changes in these arrangements under the laws appointed in the fourth creative period.
The record relating to the fourth day is silent respecting the mundane history of the period; and geology gives no very certain information concerning it. If, however, we assume that any of the Eozoic or pre-eozoic rocks are deposits of this or the preceding period, we may infer from the disturbances and alteration which these have suffered, prior to the deposition of the Cambrian and Silurian, that during or toward the close of this day the crust of the earth was affected by great movements. There is another consideration also leading to important conclusions in relation to this period. In the earliest fossiliferous rocks there seems to be good evidence that the dry land contemporary with the seas in which they were formed was of very small extent. Now, since on the third day a very plentiful and highly developed vegetation was produced, we may infer that during that period the extent of dry land was considerable, and was probably gradually increasing. If, then, the Cambrian and Silurian systems, so rich in marine organic remains, belong to the commencement of the fifth day, we must conclude that during the fourth much of the land previously existing had been again submerged. In other words, during the third day the extent of terrestrial surface was increasing, on the fourth day it diminished, and on the fifth it again increased, and probably has on the whole continued to increase up to the present time. One most important geological consequence of this is that the marine animals of the fifth day probably commenced their existence on sea bottoms which were the old soil surfaces of submerged continents previously clothed with vegetation, and which consequently contained much organic matter fitted to form a basis of support for the newly created animals.
I shall close my remarks on the fourth day by a few quotations from those passages of Scripture which refer to the objects of this day's work. I have already referred to that beautiful passage in Deuteronomy where the Israelites are warned against the crime of worshipping those heavenly bodies which the Lord God hath "divided to every nation under the whole heaven." In the book of Job also we find that the heavenly bodies were in his day regarded as signal manifestations of the power of God, and that several of the principal constellations had received names:
"He commandeth the sun, and it shineth not;
He sealeth up the stars; [91]
He alone spreadeth out the heavens,
And walketh on the high waves of the sea; [92]
He maketh Arcturus, Orion,
The Pleiades, and the hidden chambers of the south;
Who doeth great things past finding out;
Yea, marvellous things beyond number."
—Job ix., 9.
"Canst thou tighten the bonds of the Pleiades, [93]
Or loose the bands of Orion?
Canst thou bring forth the Mazzaroth in their season,
Or lead forth Arcturus and its sons?
Knowest thou the laws of the heavens,
Or hast thou appointed their dominion over the earth?"
—Job xxxviii., 31.
I may merely remark on these passages that the chambers of the south are supposed to be those parts of the southern heavens invisible in the latitude in which Job resided. The bonds of Pleiades and of Orion probably refer to the apparently close union of the stars of the former group, and the wide separation of those of the latter; a difference which, to the thoughtful observer of the heavens, is more striking than most instances of that irregular grouping of the stars which still forms a question in astronomy, from the uncertainty whether it is real, or only an optical deception arising from stars at different distances coming nearly into a line with each other. I have seen in some recent astronomical work this very instance of the Pleiades and Orion taken as a marked illustration of this problematical fact in astronomy. Mazzaroth are supposed by modern expositors to be the signs of the Zodiac.