He stretched out his hand over the sea
That is, the Lord of hosts, who had purposed to destroy Tyre, stretched out his hand of power over it, called the sea, as in ( Isaiah 23:4 ) because situated in it, supported by it, and had the sovereignty of it; in like manner as he stretched out his hand on the Red Sea, and destroyed Pharaoh and the Egyptians in it; to which the allusion may be:
he shook the kingdoms;
of Tyre and Zidon, which were both kingdoms, and distinct ones; and also made other neighbouring kingdoms shake and tremble when these fell, fearing it would be their case next. Some understand this of the moving of Nebuchadnezzar, and of the kings of the provinces under him, to come against Tyre:
the Lord hath given a commandment against the merchant [city];
the city of Tyre, so famous for merchandise, that it was the mart of nations, as in ( Isaiah 23:3 ) or "against Canaan", in which country Tyre and Zidon were, being originally built and inhabited by the posterity of Canaan, ( Genesis 10:15 Genesis 10:19 ) :
to destroy the strong holds thereof;
either of the merchant city Tyre, whose fortifications were strong, both by nature and art; or "of Canaan", whose strong holds, or fortified cities, the principal of them were Tyre and Zidon; so Jarchi: and if the Lord of hosts gives a commandment to destroy it and its strong holds, as he did to Nebuchadnezzar and his army, and afterwards to Alexander and his, who could save them? that is, God said it, who gave commandment to destroy it.