1 There are towns where the inhabitants, from dawn to eve, feast their eyes on the tricks of innumerable conjurors. They are never tired of hearing dissolute songs which cause much impurity to spring up in their souls, and they are often called happy, because they neglect the cares of business and trades useful to life, and pass the time, which is assigned to them on this earth, in idleness and pleasure. They do not know that a theatre full of impure sights is, for those who sit there, a common school of vice; that these melodious and meretricious songs insinuate themselves into men's souls, and all who hear them, eager to imitate the notes of harpers and pipers, are filled with filthiness. Some others, who are wild after horses, think they are backing their horses in their dreams; they harness their chariots, change their drivers, and even in sleep are not free from the folly of the day. And shall we, whom the Lord, the great worker of marvels, calls to the contemplation of His own works, tire of looking at them, or be slow to hear the words of the Holy Spirit? Shall we not rather stand around the vast and varied workshop of divine creation and, carried back in mind to the times of old, shall we not view all the order of creation? Heaven, poised like a dome, to quote the words of the prophet; earth, this immense mass which rests upon itself; the air around it, of a soft and fluid nature, a true and continual nourishment for all who breathe it, of such tenuity that it yields and opens at the least movement of the body, opposing no resistance to our motions, while, in a moment, it streams back to its place, behind those who cleave it; water, finally, that supplies drink for man, or may be designed for our other needs, and the marvellous gathering together of it into definite places which have been assigned to it: such is the spectacle which the words which I have just read will show you.
2. “And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear, and it was so.” And the water which was under the heaven gathered together unto one place; “And God called the dry land earth and the gathering together of the waters called He seas.” What trouble you have given me in my previous discourses by asking me why the earth was invisible, why all bodies are naturally endued with colour, and why all colour comes under the sense of sight. And, perhaps, my reason did not appear sufficient to you, when I said that the earth, without being naturally invisible, was so to us, because of the mass of water that entirely covered it. Hear then how Scripture explains itself. “Let the waters be gathered together, and let the dry land appear.” The veil is lifted and allows the earth, hitherto invisible, to be seen. Perhaps you will ask me new questions. And first, is it not a law of nature that water flows downwards? Why, then, does Scripture refer this to the fiat of the Creator? As long as water is spread over a level surface, it does not flow; it is immovable. But when it finds any slope, immediately the foremost portion falls, then the one that follows takes its place, and that one is itself replaced by a third. Thus incessantly they flow, pressing the one on the other, and the rapidity of their course is in proportion to the mass of water that is being carried, and the declivity down which it is borne. If such is the nature of water, it was supererogatory to command it to gather into one place. It was bound, on account of its natural instability, to fall into the most hollow part of the earth and not to stop until the levelling of its surface. We see how there is nothing so level as the surface of water. Besides, they add, how did the waters receive an order to gather into one place, when we see several seas, separated from each other by the greatest distances? To the first question I reply: Since God's command, you know perfectly well the motion of water; you know that it is unsteady and unstable and falls naturally over declivities and into hollow places. But what was its nature before this command made it take its course? You do not know yourself, and you have heard from no eye-witness. Think, in reality, that a word of God makes the nature, and that this order is for the creature a direction for its future course. There was only one creation of day and night, and since that moment they have incessantly succeeded each other and divided time into equal parts.
3. “Let the waters be gathered together.” It was ordered that it should be the natural property of water to flow, and in obedience to this order, the waters are never weary in their course. In speaking thus, I have only in view the flowing property of waters. Some flow of their own accord like springs and rivers, others are collected and stationary. But I speak now of flowing waters. “Let the waters be gathered together unto one place.” Have you never thought, when standing near a spring which is sending forth water abundantly, Who makes this water spring from the bowels of the earth? Who forced it up? Where are the store-houses which send it forth? To what place is it hastening? How is it that it is never exhausted here, and never overflows there? All this comes from that first command; it was for the waters a signal for their course.
In all the story of the waters remember this first order, “let the waters be gathered together.” To take their assigned places they were obliged to flow, and, once arrived there, to remain in their place and not to go farther. Thus in the language of Ecclesiastes, “All the waters run into the sea; yet the sea is not full.” Waters flow in virtue of God's order, and the sea is enclosed in limits according to this first law, “Let the waters be gathered together unto one place.” For fear the water should spread beyond its bed, and in its successive invasions cover one by one all countries, and end by flooding the whole earth, it received the order to gather unto one place. Thus we often see the furious sea raising mighty waves to the heaven, and, when once it has touched the shore, break its impetuosity in foam and retire. “Fear ye not me, says the Lord....which have placed the sand for the bound of the sea.” A grain of sand, the weakest thing possible, curbs the violence of the ocean. For what would prevent the Red Sea from invading the whole of Egypt, which lies lower, and uniting itself to the other sea which bathes its shores, were it not fettered by the fiat of the Creator? And if I say that Egypt is lower than the Red Sea, it is because experience has convinced us of it every time that an attempt has been made to join the sea of Egypt to the Indian Ocean, of which the Red Sea is a part. Thus we have renounced this enterprise, as also have the Egyptian Sesostris, who conceived the idea, and Darius the Mede who afterwards wished to carry it out.
I report this fact to make you understand the full force of the command, “Let the waters be gathered unto one place”; that is to say, let there be no other gathering, and, once gathered, let them not disperse.
Source: Nine Homilies of Hexaemeron (New Advent)