15. Thou hast redeemed thy people by thy arm. The Psalmist here celebrates, above all the other wonderful works of God, the redemption of the chosen people, to which the Holy Spirit everywhere throughout the Scriptures invites the attention of true believers, in order to encourage them to cherish the hope of their salvation. It is well known that the power of God was at that time manifested to the Gentiles. The truth of history, indeed, through the artifice of Satan, was corrupted and falsified by many fables; but this is to be imputed to the wickedness of those in whose sight those wonderful works were wrought, who, although they saw them, chose rather to blind their eyes and disguise the truth of their existence, than to preserve the true knowledge of them.¹ How can we explain the fact that they made Moses to be I know not what kind of a magician or enchanter, and invented so many strange and monstrous stories, which Josephus has collected together in his work against Apion, but upon the principle that it was their deliberate purpose to bury in forgetfulness the power of God? It is not, however, so much the design of the prophet to condemn the Gentiles of the sin of ingratitude, as to furnish himself and others of the children of God matter of hope as to their own circumstances; for at the time referred to, God openly exhibited for the benefit of all future ages a proof of his love towards his chosen people. The word arm is here put metaphorically for power of an extraordinary character, and which is worthy of remembrance. God did not deliver his ancient people secretly and in an ordinary way, but openly, and, as it were, with his arm stretched forth. The prophet, by calling the chosen tribes the sons of Jacob and Joseph, assigns the reason why God accounted them as his people. The reason is, because of the covenant into which he entered with their godly ancestors. The two tribes which descended from the two sons of Joseph derived their origin from Jacob as well as the rest; but the name of Joseph is expressed to put honor upon him, by whose instrumentality the whole race of Abraham were preserved in safety.²

16. The waters saw thee, O God! Some of the miracles in which God had displayed the power of his arm are here briefly adverted to. When it is said that the waters saw God, the language is figurative, implying that they were moved, as it were, by a secret instinct and impulse to obey the divine command in opening up a passage for the chosen people. Neither the sea nor the Jordan would have altered their nature, and by giving place have spontaneously afforded a passage to them, had they not both felt upon them the power of God.³ It is not meant that they retired backward because of any judgment and understanding which they possessed, but that in receding as they did, God showed that even the inanimate elements are ready to yield obedience to him. There is here an indirect contrast, it being intended to rebuke the stupidity of men if they do not acknowledge in the redemption of the Israelites from Egypt the presence and hand of God, which were seen even by the waters. What is added concerning the deeps intimates, that not only the surface of the waters were agitated at the sight of God, but that his power penetrated even to the deepest gulfs.

17. The clouds poured out waters. As the noun Mym, mayim, cannot be taken in the construct state, the verb, I have no doubt, is put transitively; but it makes little difference as to the sense, whether we take this view, or read as if Mym, mayim, were in the construct state and the verb passive; that is, whether we read, The clouds poured out waters, or, The waters of the clouds were poured out. The meaning obviously is, that not only the sea and the river Jordan, but also the waters which were suspended in the clouds, yielded to God the honor to which he is entitled, the air, by the concussion of the thunder, having poured forth copious showers. The object is to show, that, to whatever quarter men turn their eyes, the glory of God is illustriously manifested, that it is so in every part of creation, above and beneath, from the height of heaven to the depths of the sea. What history is here referred to is involved in some degree of uncertainty.⁴ Perhaps it is that which is recorded in Exodus 9:23; where we are informed, that hail mingled with thunder and lightning was one of the dreadful plagues inflicted upon the Egyptians. The arrows which went abroad are, no doubt, to be taken metaphorically for lightnings. With this verse we are to connect the following, in which it is said, that the voice of the thunder was heard in the air, and that the lightnings illumined the world, so that the earth trembled. The amount is, that at the departure of the people from Egypt, ample testimony was borne to the power of God, both to the eyes and the ears of men; peals of thunder having been heard in every quarter of the heavens, and the whole sky having shone with flashes of lightning, while at the same time the earth was made to tremble.

19. Thy ways are in the sea. The miracle which was wrought in drying up the Red Sea is here again described in different phraseology. What, properly speaking, refers to the Israelites is applied to God, under whose protection and guidance they passed dry-shod through the midst of the Red Sea. It is declared that a path had been opened up for them in a very strange and unusual manner; for the sea was not drained by the skill of man, nor was the river Jordan turned aside from its ordinary course into a different channel, but the people walked through the midst of the waters in which Pharaoh and his whole army were soon after drowned. On this account, it is said, that the footsteps of God were not known, for no sooner had God made the people to pass over than he caused the waters to return to their accustomed course.⁵

The purpose for which this was effected is added in the 20th verse, -- the deliverance of the Church: Thou didst lead thy people like a flock.⁶ And this deliverance should be regarded by all the godly as affording them the best encouragement to cherish the hope of safety and salvation. The comparison of the people to sheep, tacitly intimates that they were in themselves entirely destitute of wisdom, power, and courage, and that God, in his great goodness, condescended to perform the office of a shepherd in leading through the sea, and the wilderness, and all other impediments, his poor flock, which were destitute of all things, that he might put them in possession of the promised inheritance. This statement is confirmed, when we are told that Moses and Aaron were the persons employed in conducting the people. Their service was no doubt illustrious and worthy of being remembered; but God displayed in no small degree the greatness of his power in opposing two obscure and despised individuals to the fury and to the great and powerful army of one of the proudest kings who ever sat on a throne. What could the rod of an outlaw and a fugitive, and the voice of a poor slave, have done of themselves, against a formidable tyrant and a warlike nation? The power of God then was the more manifest when it wrought in such earthen vessels. At the same time, I do not deny that it is here intended to commend these servants of God, to whom he had committed such an honorable trust.