to His omnipotent will, but caused them to be produced by Moses and Aaron and disappear again at their word and prayer, that Pharaoh might learn that these men were appointed by Him as His messengers, and were endowed by Him with divine power for the accomplishment of His will.
verses 14-21
The Water of the Nile Turned into Blood. - In the morning, when Pharaoh went to the Nile, Moses took his staff at the command of God; went up to him on the bank of the river, with the demand of Jehovah that he would let His people Israel go; and because hitherto (עד־כּה) he had not obeyed, announced this first plague, which Aaron immediately brought to pass. Both time and place are of significance here. Pharaoh went out in the morning to the Nile (Exo 7:15; Exo 8:20), not merely to take a refreshing walk, or to bathe in the river, or to see how high the water had risen, but without doubt to present his daily worship to the Nile, which was honoured by the Egyptians as their supreme deity (vid., Exo 2:5). At this very moment the will of God with regard to Israel was declared to him; and for his refusal to comply with the will of the Lord as thus revealed to him, the smiting of the Nile with the staff made known to him the fact, that the God of the Hebrews was the true God, and possessed the power to turn the fertilizing water of this object of their highest worship into blood. The changing of the water into blood is to be interpreted in the same sense as in Joe 3:4, where the moon is said to be turned into blood; that is to say, not as a chemical change into real blood, but as a change in the colour, which caused it to assume the appearance of blood (2Ki 3:22). According to the statements of many travellers, the Nile water changes its colour when the water is lowest, assumes first of all a greenish hue and is almost undrinkable, and then, while it is rising, becomes as red as ochre, when it is more wholesome again. The causes of this change have not been sufficiently investigated. The reddening of the water is attributed by many to the red earth, which the river brings down from Sennaar (cf. Hengstenberg, Egypt and the Books of Moses, pp. 104ff. transl.; Laborde, comment. p. 28); but Ehrenberg came to the conclusion, after microscopical examinations, that it was caused by cryptogamic plants and infusoria. This natural phenomenon was here intensified into a miracle, not
