Revelation 16:3

And the second angel poured out his vial upon the sea
Not literally; and so does not design the stagnation of it, which it is thought will be before the general conflagration; see ( Amos 7:4 ) nor is it to be understood of the sea of this world, and the men of it, who are like a troubled sea; but rather of Popish doctrines and councils, which are a sea of errors, and will now be confuted and put an end to. Brightman applies it to the council of Trent, and makes this angel to be Chemnitius, a German divine, who wrote a confutation of it; but as the sea is a collection of many waters, and many waters in this book signify the people and nations under the Romish yoke, sea here may design the whole jurisdiction of Rome, or mystical Babylon; see ( Jeremiah 51:36 ) and particularly its maritime powers, Spain and Portugal: and as the second trumpet affected the sea, ( Revelation 8:8 ) and brought the Vandals into Spain and Portugal, so this second vial affects the sea, and brings great wars, slaughter, and bloodshed into these parts, when they also will be reformed from Popery:

and it became as the blood of a dead man;
thick, clotted together, and putrid, and so never to be returned to their former state:

and every living soul died in the sea:
those, that are not reformed will either die by the sword, or fly into other parts; for there will be no comfortable living for the Popish party in those countries where now they live in power, ease, and affluence. This, and the following vial, are referred by Mr. Daubuz, the one to the first crusades, or holy wars, for the regaining of the holy land, and the other to the latter of them.