The seed beast represented zealot led Israel. Please read Adam Maarschalk's article on the beast here- https://adammaarschalk.com/2017/04/09/who-was-the-beast-five-clues-long-island-conference-presentation/ And his article on Daniel seven explains the sea beast. https://adammaarschalk.com/2017/01/14/daniel-7-the-fourth-beast-10-horns-three-horns-and-a-little-horn/
Most tend to read this and envisage a literal 'Great Sea'. However, it refers to a biblical sea, a sea also symbolized by the bronze sea located in the temple of Solomon.
1King 7:23 And he made the Sea of cast bronze, ten cubits from one brim to the other; it was completely round. Its height was five cubits, and a line of thirty cubits measured its circumference. :24 Below its brim were ornamental buds encircling it all around, ten to a cubit, all the way around the Sea. The ornamental buds were cast in two rows when it was cast. :25 It stood on twelve oxen: three looking toward the north, three looking toward the west, three looking toward the south, and three looking toward the east; the Sea was set upon them, and all their back parts pointed inward. :26 It was a handbreadth thick; and its brim was shaped like the brim of a cup, like a lily blossom. It contained two thousand baths. :39 ... He set the Sea on the right side of the house, toward the southeast. This bronze sea was placed upon 12 bronze oxen. Oxen which faced toward the four directions of heaven; north, west, south and east. Three oxen facing each direction. [ NB: The arrangement of the oxen mimics that of the 12 tribes of the children of Israel, which were to stand 3 tribes in each direction around the tabernacle of meeting. Refer, Numbers chapter 2. ] THE GREAT SEA - The great sea represents the multitude of people supported by the national structure of the 12 tribes. (Note, Jude 13 where 'raging waves of the sea' represents people. Also in Rev 17:15 we observe the symbol 'waters' used to represent groups of people.) The four beasts which arise from this Great Sea, arise out of Israel! Hence, depicting four different 'kingdom' forms of Israel. To try and identify the four beasts, one has to reflect upon the biblical history of Israel and also consider other relevant prophecies.
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