Get thee unto Pharaoh in the morning; lo, he goeth out unto the water; and thou shalt stand by {e} the river's brink against he come; and the rod which was turned to a serpent shalt thou take in thine hand.

(e) That is, the Nile river.

Jamieson-Fausset-Brown Bible Commentary

15. Get thee unto Pharaoh-Now began those appalling miracles of judgment by which the God of Israel, through His ambassadors, proved His sole and unchallengeable supremacy over all the gods of Egypt, and which were the natural phenomena of Egypt, at an unusual season, and in a miraculous degree of intensity. The court of Egypt, whether held at Rameses, or Memphis, or Tanis in the field of Zoan (Ps 78:12), was the scene of those extraordinary transactions, and Moses must have resided during that terrible period in the immediate neighborhood.

in the morning; lo, he goeth out unto the water-for the purpose of ablutions or devotions perhaps; for the Nile was an object of superstitious reverence, the patron deity of the country. It might be that Moses had been denied admission into the palace; but be that as it may, the river was to be the subject of the first plague, and therefore, he was ordered to repair to its banks with the miracle-working rod, now to be raised, not in demonstration, but in judgment, if the refractory spirit of the king should still refuse consent to Israel's departure for their sacred rites.

Matthew Henry's Concise Commentary

7:14-25 Here is the first of the ten plagues, the turning of the water into blood. It was a dreadful plague. The sight of such vast rolling streams of blood could not but strike horror. Nothing is more common than water: so wisely has Providence ordered it, and so kindly, that what is so needful and serviceable to the comfort of human life, should be cheap and almost every where to be had; but now the Egyptians must either drink blood, or die for thirst. Egypt was a pleasant land, but the dead fish and blood now rendered it very unpleasant. It was a righteous plague, and justly sent upon the Egyptians; for Nile, the river of Egypt, was their idol. That creature which we idolize, God justly takes from us, or makes bitter to us. They had stained the river with the blood of the Hebrews' children, and now God made that river all blood. Never any thirsted after blood, but sooner or later they had enough of it. It was a significant plague; Egypt had great dependence upon their river, Zec 14:18; so that in smiting the river, they were warned of the destruction of all the produce of their country. The love of Christ to his disciples changes all their common mercies into spiritual blessings; the anger of God towards his enemies, renders their most valued advantages a curse and a misery to them. Aaron is to summon the plague by smiting the river with his rod. It was done in the sight of Pharaoh and his attendants, for God's true miracles were not performed as Satan's lying wonders; truth seeks no corners. See the almighty power of God. Every creature is that to us which he makes it to be water or blood. See what changes we may meet with in the things of this world; what is always vain, may soon become vexatious. See what mischievous work sin makes. If the things that have been our comforts prove our crosses, we must thank ourselves. It is sin that turns our waters into blood. The plague continued seven days; and in all that time Pharaoh's proud heart would not let him desire Moses to pray for the removal of it. Thus the hypocrites in heart heap up wrath. No wonder that God's anger is not turned away, but that his hand is stretched out still.