Matthew Poole and continuators on Isaiah 23:3

3 And by great waters the seed of Sihor , the harvest of the river is her revenue , and she is a mart of nations .

By the Sea, which is very fitly called the great waters, Psal. 107. 23. understand, cometh, or is brought to her.

The Corn of Egypt, wherewith Egypt abounded, and furnished divers other Parts of the World, whence it was called the Granary of the Roman Empire; which also was easily conveyed by Sea from Egypt to Tyre, and thence to divers other Countries. This is called seed here, as also Hag. 2. 19. and elsewhere, by an usual Metonymy; and the seed of Sihor, because it grew up the more abundantly because of the Overflow of the River, as all sorts of Authors have noted. For Sihor is nothing else but Nilus, as appears from Ier. 2. 18. which is called Sihor, as by the Greeks it was called Melas, from its black Colour. And this and no other River seems to be that Sihor which is so oft mentioned as one of the Bounds of the Land of Canaan, as Numb. 34. 5. &c. because that Land, at least in that extent which God allotted and gave it to the Israelites, though they through neglect or cowardise might not actually possess it, did reach to one of the Branches of that River: And indeed, if Sihor be not Nilus, that great and neighbouring River is not named in all the Scripture, which seems very improbable.

This Clause explains the former; that plentiful Harvest of Corn which comes from the Influence and Inundation of Nilus, which is emphatically called the river, as here, so also Exod. 1. 22. Isa. 19. 5. Ezek. 29. 3, 9. as Euphrates is in other Texts of Scripture.

Is as easily procured, and plentifully enjoyed by her, as if it grew in her own Territories.

A Place to which all Nations resort for Traffick.