And the second angel sounded, and as it were a great mountain burning with fire was cast into the sea: and the third part of the sea became blood;
As it were - not literally: a mountain-like burning mass: in allusion to Jeremiah 51:25; Amos 7:4.
Third part of the sea became blood. In the parallel second vial, the whole sea becomes blood. The overthrow of Jericho (type of the anti-Christian Babylon), after which Israel under Joshua (Jesus) took possession of Canaan (type of Christ's and His people's kingdom), is perhaps alluded to in the SEVEN trumpets, which end in the overthrow of Christ's foes, and the setting up of His kingdom. On the seventh day, at the seventh time, when the seven priests blew the seven rams' horn trumpets, the people shouted, and the walls fell flat; then ensued the blood-shedding of the foe. A mountain-like fiery mass would not naturally change water into blood; nor would the third of ships be destroyed. Symbolical interpreters take ships here to be churches. For х ploion (G4143)] "ships" is in the gospels the term for the apostolic vessel in which Christ taught. The first churches were in the shape of an inverted ship; and х diefthareesan (G1311)] destroyed is used of heretical corruptings (1 Timothy 6:5).