And the Lord spake, &c.— Pharaoh despising the Divine threatening, the Lord orders Moses to put it into execution: and Aaron is accordingly commanded to stretch out his hand upon the waters of Egypt; that is, not to stretch out his hand over all the waters of Egypt; but to stretch it out in token of the Divine malediction which was immediately to operate upon the waters.
Upon the waters, &c.— Travellers tell us, that it is common for the Nile-water to turn red and become disagreeable in one part of the year; whence, perhaps, some may imagine, that this corruption of the waters was only a natural occurrence: but, besides the event's taking place before the usual time, immediately upon the smiting of the river by Moses and Aaron, and its being followed by other wonders; the universality of the corruption, and the effects it produced, evidently shew the finger of God. Let us consider the universality of it with a little distinctness: a variety of words are made use of to set it forth, nor is that variety made use of without a meaning. The Nile was the only river in Egypt; but it was divided into branches, and entered by several mouths into the sea. Numberless canals were formed by art for better watering the lands; several vast lakes, by the Nile's inundations; and many reservoirs, for retaining the water, in order to the watering the gardens and plantations, or having sweet water when the river corrupts.
All these seem to be distinctly pointed out in the text: the words of which, however, in our versions are not so well chosen as might be wished, nor so happily selected as those of the translation of Pagninus and Arius Montanus, which runs thus: super flumina—rivos—paludes—omnem congregationem aquarum: upon their rivers, (or branches of their river,) their canals—their lakes, or large standing waters—and all reservoirs of water of a smaller kind. Now, had it been a natural event, the lakes and reservoirs, which had then no communication with the river, on account of the lowness of the water at that time of the year, could not have been infected; which yet they were, according to the Mosaic history; and they were forced to dig wells, instead of resorting to their wonted reservoirs. The effects which the corruption produced, prove the same thing in the second place. Had it been a sort of corruption which happened not unfrequently, would the Egyptians have been surprised at it? or would their magicians have attempted to imitate it? would they not rather have shewn it to be a natural and common event? and is the common corruption such as kills the fish in the Nile? That in the time of Moses did; but nothing of that sort appears in modern travels. We see then, that a variety of evident circumstances concur to determine it a miracle.
Both in vessels of wood and in vessels of stone— "To what purpose," says the Author of the Observations, "is this minuteness? this corrupting the waters which had been taken up into vessels before the stretching out the fatal rod? and, if vessels are mentioned at all, why are those of wood and stone distinguished from each other?—But perhaps these words do not signify, that the water, which had been taken up into their vessels, was changed into blood. The water of the Nile is known to be very thick and muddy; and they purify it either by a paste made of almonds, or by filtrating it through certain pots made of white earth, which, it seems, is the preferable way; and therefore the possession of one of these pots is thought a great happiness; see Le Bruyn, tom. 2: p. 103 and Thevenot, part 1: p. 245 and 260. Now, may not the meaning of this passage be, that the water of the Nile should not only look red and nauseous like blood, in the river, but in their vessels too, when taken up in small quantities; and that no method whatever of purifying it should take place; but whether drank out of vessels of wood, or out of vessels of stone, (by means of which they were wont to purge the Nile-water) it should be the same, and should appear like blood? There is no doubt but they were accustomed, even in early days, to clarify the water of the Nile; and the merely letting it stand to settle, was hardly sufficient for the early elegance which obtained in Egypt. So simple a method then, as filtrating vessels, may easily be supposed to be as ancient as the times of Moses; and therefore it seems natural to suppose, that partly to them the threatening in the text refers."