13. Thou hast divided the sea by thy power: thou hast broken the heads of the dragons upon the waters.14. Thou hast broken the head of Leviathan in pieces, and hast given him for food to thy people in the wilderness.15. Thou hast cleaved [or divided] the fountain and the torrent: thou hast dried up mighty rivers.16. The day is thine, the night also is thine: thou hast ordained the light and the sun.17. Thou hast set [or fixed] all the boundaries of the earth: thou hast made the summer and the winter.
13. Thou hast divided the sea by thy power. The prophet now collects together certain kinds of deliverances highly worthy of remembrance; all of them, however, belonging to the first deliverance by which God emancipated his people from the tyranny of Egypt. We will find him afterwards descending to the general commendation of the goodness of God which is diffused through the whole world. Thus from the special grace which God vouchsafes to his Church, he passes on to speak of the good-will which he displays towards all mankind. In the first place, he says, Thou hast divided, or cleaved, the sea. Some think that the following clause is subjoined as an effect of what is stated in the first clause, -- God, by drying up the sea, having caused the whales and other great fishes to die. I am, however, of opinion, that it is to be taken metaphorically for Pharaoh and his army; this mode of expression being very common among the prophets, especially when they speak of the Egyptians, whose country was washed by a sea abounding with fish, and divided by the Nile. Pharaoh is, therefore, not improperly termed Leviathan, on account of the advantages of the sea possessed by his country, and because, in reigning over that land with great splendor, he might be compared to a whale moving up and down at its ease in the midst of the waters of the mighty ocean. As God put forth his power at that time for the deliverance of the people, to assure the Church that he would always be her protector and the guardian of her welfare, the encouragement afforded by this example ought not to be limited exclusively to one age. It is, therefore, with good reason applied to the descendants of that ancient race, that they might improve it as a means of confirming and establishing their faith. The prophet does not here recount all the miracles which God had wrought at the departure of the people from the land of Egypt; but in adverting to some of them, he comprehends by the figure synecdoche, all that Moses has narrated concerning them at greater length. When he says that leviathan was given for food to the Israelites, and that even in the wilderness, there is a beautiful allusion to the destruction of Pharaoh and his host. It is as if he had said, that then a bountiful provision of victuals was laid up for the nourishment of the people; for when their enemies were destroyed, the quiet and security which the people in consequence enjoyed served, so to speak, as food to prolong their life. By the wilderness, is not meant the countries lying on the sea coast, though they are dry and barren, but the deserts at a great distance from the sea. The same subject is prosecuted in the following verse, where it is declared, that the fountain was cleaved or divided, that is, it was so when God caused a stream of water to gush from the rock to supply the wants of the people. Finally, it is added, that mighty rivers were dried up, an event which happened when God caused the waters of the Jordan to turn back to make a way for his people to pass over. Some would have the Hebrew word 'ytn, ethan, which signifies mighty, to be a proper name, as if the correct translation were rivers of Ethan; but this interpretation is altogether without foundation.
16. The day is thine, the night also is thine. The prophet now descends to the consideration of the divine benefits which are extended in common to all mankind. Having commenced with the special blessings by which God manifested himself to be the Father of his chosen people, he now aptly declares that God exercises his beneficence towards the whole human family. He teaches us, that it is not by chance that the days and nights succeed each other in regular succession, but that this order was established by the appointment of God. The secondary cause of these phenomena is added, being that arrangement by which God has invested the sun with the power and office of illuminating the earth; for after having spoken of the light he adds the sun, as the principal means of communicating it, and, so to speak, the chariot in which it is brought when it comes to show itself to men. As then the incomparable goodness of God towards the human race clearly shines forth in this beautiful arrangement, the prophet justly derives from it an argument for strengthening and establishing his trust in God.
17. Thou hast fixed all the boundaries of the earth. What is here stated concerning the boundaries or limits assigned to the earth, and concerning the regular and successive recurrence of summer and winter every year, is to the same effect as the preceding verse. It is doubtful whether the prophet means the uttermost ends of the world, or whether he speaks of the particular boundaries by which countries are separate from each other. Although the latter are often disturbed by the violence of men, whose insatiable cupidity and ambition cannot be restrained by any of the lines of demarcation which exist in the world, but are always endeavoring to break through them; yet God manifests his singular goodness in assigning to each nation its own territory upon which to dwell. I am, however, rather of opinion, that the clause is to be understood of those bounds which cannot be confounded at the will of men, and consider the meaning to be, that God has allotted to men as much space of earth as he has seen to be sufficient for them to dwell upon. Farther, the well regulated successions of summer and winter clearly indicate with what care and benignity God has provided for the necessities of the human family. From this, the prophet justly concludes, that nothing is more improbable than that God should neglect to act the part of a father towards his own flock and household.