To add to the understanding of the dragon/serpent of seven heads Leviathan which rise up off of the sea. As we have noted that the sea is used to denote evil and choas by the tossing back and forth motion. It is also associated with the deep and darkness as if it was a bottomless pit. The sea is a mysterious and unstable, and constantly changing forces in the world. The sea has no end to it's depth and disappears into a watery abyss. The sea can produce waves that shallow and destory ships and brings floods upon the land.
It is in this sence that the writers often used the sea and the dragon to denote an evil nation and it's king. For instance Isaiah and Ezekiel mention about Egypt , Assyria and it's connection to the dragon and Rahab.
3Speak, and say, Thus saith the Lord GOD; Behold, I am against thee, Pharaoh king of Egypt, the great dragon that lieth in the midst of his rivers, which hath said, My river is mine own, and I have made it for myself.
4But I will put hooks in thy jaws, and I will cause the fish of thy rivers to stick unto thy scales, and I will bring thee up out of the midst of thy rivers, and all the fish of thy rivers shall stick unto thy scales.
5And I will leave thee thrown into the wilderness, thee and all the fish of thy rivers: thou shalt fall upon the open fields; thou shalt not be brought together, nor gathered: I have given thee for meat to the beasts of the field and to the fowls of the heaven.
2Son of man, take up a lamentation for Pharaoh king of Egypt, and say unto him, Thou art like a young lion of the nations, and thou art as a whale in the seas: and thou camest forth with thy rivers, and troubledst the waters with thy feet, and fouledst their rivers. 3Thus saith the Lord GOD; I will therefore spread out my net over thee with a company of many people; and they shall bring thee up in my net
34Nebuchadrezzar the king of Babylon hath devoured me, he hath crushed me, he hath made me an empty vessel, he hath swallowed me up like a dragon, he hath filled his belly with my delicates, he hath cast me out.
5The LORD spake also unto me again, saying,
6Forasmuch as this people refuseth the waters of Shiloah that go softly, and rejoice in Rezin and Remaliah's son;
7Now therefore, behold, the Lord bringeth up upon them the waters of the river, strong and many, even the king of Assyria, and all his glory: and he shall come up over all his channels, and go over all his banks: 8And he shall pass through Judah; he shall overflow and go over, he shall reach even to the neck; and the stretching out of his wings shall fill the breadth of thy land, O Immanuel.
Therefore the seven headed beast of Revelation 13 represents the completion of the seven literal nations and their kings that should come out of the sea. There is no reason to assume that the seven heads are seven 'hills' of Rome. Hills or Mountains have been shown by Daniel to be kingdoms and not to denote any city that has hills. Some scholars claim that the seven 'hill's is to refer to Rome seven hills as the seven heads then claim that the seven kings are the seven Caesars.
Among the many problems with this view is the fact that there were far more than seven Caesars. With which Caesar do you begin? And with which one do you end? Who are the five Caesars who had fallen? Who was the one still ruling? Who was the one who had not yet come? Some of the Caesars ruled for long periods, some for a few months. After the death of Nero, three Caesars ruled within a two-year period, each being murdered.
Following the death of Alexander the Great, the Grecian Empire, over which he had ruled, was divided into four parts. Each part, though part of the whole of the Grecian Empire, was its own kingdom. This division of the Greek Empire into four parts is depicted in Daniel 7:6 as a leopard with four wings.
The leopard with four wings represents Alexander and his rapid conquest of much of the world. And the four heads of the leopard represent the division of his empire into four kingdoms ruled over by four of Alexander's generals. Cassander ruled over Macedonia, Lysimachus ruled over Thrace and Asia Minor, Seleucus ruled over Syria and Babylonia, and Ptolemy ruled over Egypt and Arabia.
The four "heads" on the beast represented four kingdoms which were part of the divided Grecian Empire (Dan. 8:21-22). John was told that the seven heads of the beast of Revelation 17 are seven mountains. Since we are told that heads equal kingdoms and heads are specifically said to be mountains then mountains should equal kingdoms.
King David, in speaking of all the vicissitudes of his reign as king of Israel, wrote, "LORD, by thy favour thou hast made my mountain [kingdom] to stand strong"