John Calvin on Isaiah 23:6

6. Pass ye over to Tarshish. He addresses not only the inhabitants of Tyre, but foreigners who were connected with them by trading, and bids them go elsewhere and seek new harbours: and he mentions Cilicia, which was opposite to Tyre, as if he had said, “That shore, which was wont to be well supplied with harbours, will henceforth be forsaken, so that ships will sail in a very different direction;” for when a harbour or a mercantile city has been ruined, merchants commonly go in search of another.

Howl, ye inhabitants of the island. {Bogus footnote} “Island,” as we have formerly explained, is here put for “islands;” for the change of number is very customary with Hebrew writers. He foretells that they will lament, because their support depended entirely on that traffic, and because their accounts and reckonings {Bogus footnote} were scattered about in all directions.