Job 40:22 - Matthew Poole's English Annotations on the Holy Bible

Of the brook; or, of Nilus, of which this word is oft used in Scripture. And this seems to be the chief argument by which the learned Bochart proves this to be meant of the hippopotamus, whose constant residence is in or near the river of Nilus, or the willows that grow by it. But it is well alleged by our learned and judicious Caryl, that this word Naal is never used to express Nilus when it is put by itself, as here it is, but only where the word Egypt is added to it, as it is in all the places which Bochart produceth. And this very phrase, the willows of the brook, is used of other brooks or rivers besides Nilus, as Leviticus 23:40: compare Isaiah 15:7.