Charles H. Spurgeon on Psalms 105:29

He turned their waters into blood, etc. The Nile begins to rise about the end of June, and attains its highest point at the end of September. About the commencement of the rise it assumes a greenish hue, is disagreeable to the taste, unwholesome, and often totally unfit for drinking. It soon, however, becomes red and turbid, and continues in this state for three or more weeks. In this condition it is again healthy and fit for use. The miracle now performed was totally different from this annual change. For,

1. It occurred after the winter, not the summer, solstice;

2. The water was turned into blood, and not merely reddened by an admixture of red clay or animalcule;

3. The fish died, a result which did not follow from the periodical change of colour;

4. The river stank, and became offensive, which it ceased to be when the ordinary redness made its appearance;

5. The stroke was arrested at the end of seven days, whereas the natural redness continued for at least three weeks; and

6. The change was brought on instantly at the word of command before the eyes of Pharaoh. The calamity was appalling. The sweet waters of the Nile were the common beverage of Egypt. It abounded in all kinds of fish, which formed a principal article of diet for the inhabitants. It was revered as a god by Egypt. But now it was a putrid flood, from which they turned away with loathing. James G. Murphy.