3. The plagues followed the pattern of the experiences of the Israelites in Egypt, as indicated in verses three through four; and Pharaoh Rameses, the oppressor of Israel, parallels Nero Caesar, the imperial persecutor of the church. It again presented the comparison of the old testament and new testament people of God--Israel and the Church.
(2) The sea of dead blood which putrified the society of imperial idolatry: “ And the second angel poured out his vial upon the sea; and it became as the blood of a dead man: and every living soul died in the sea."--16:3.
In accordance with the definitions of the symbols in the first section, the sea represented society in various descriptions- tossed and troubled, or placid and peaceful. Here the sea became as the blood of a dead man--signifying the complete dissolution of the emperor-beast and his subject.