Though earth can be used in a global sense, throughout the Bible earth often just means land. In other words, when the Bible uses the word earth it often just represents the people of a particular city or kingdom as is exemplified in Isaiah 1:1-3 and Isaiah 24-27:
The vision concerning Judah and Jerusalem that Isaiah son of Amoz saw during the reigns of Uzziah, Jotham, Ahaz and Hezekiah, kings of Judah. A Rebellious Nation Hear me, you heavens! Listen, earth! For the Lord has spoken: “I reared children and brought them up, but they have rebelled against me. The ox knows its master, the donkey its owner’s manger, but Israel does not know, my people do not understand (Isaiah 1:1-3).”
In the verses above, it is clear that Isaiah’s audience which is called the earth in v. 2 is clearly Israel. Here earth is used in a local sense to just refer to Israel. The fact that earth is often used in a local sense like the word land is illustrated perhaps even clearer in Jeremiah 51:24-25: “’Before your eyes I will repay Babylon and all who live in Babylonia for all the wrong they have done in Zion,’ declares the Lord. ‘I am against you, you destroying mountain [Babylon], you who destroy the whole earth,’ declares the Lord.” Throughout the Bible mountain often means a city or kingdom since fortified cities were often built on mountains (Psalms 2:6; 48:1; Isaiah 66:20; Jeremiah 51:25; Daniel 9:16; Joel 3:17). Though Babylon, the “destroying mountain” of v. 25, had a large empire that stretched across much of the Middle East and small parts of North Africa, it certainly did not conquer or destroy the entire planet. Thus in v. 25 earth is used in a local sense. From the immediate context earth appears to just signify Jerusalem addressed as Mt. Zion in v. 24.
Throughout the Bible, earth often symbolizes a particular nation or kingdom and sea represent nations foreign to the specific nation addressed as the earth. In Daniel 7, four beasts are said to arise out of the sea. These four beasts symbolize Babylon, Medo-Persia, Greece and Rome—all Gentile empires. Revelation 17:15 also clearly exemplifies the fact that sea or waters represents foreign nations: “The waters you saw, where the prostitute sits, are peoples, multitudes, nations and languages.” There are many other examples in the Bible in which words like sea or waters clearly represent nations foreign to the specific kingdom addressed (Daniel 7; 9:26; 11:10, 40; Psalm 65:7; 144:7, Isaiah 8:7-8; 17:12; 60:5; Jeremiah 46:7-8; 47:1-2; 51:55-56; Ezekiel 26:3; Nahum 1:8):
Reach down your hand from on high; deliver me and rescue me from the mighty waters, from the hands of foreigners[.]” (Psalm 144:7)
Woe to the many nations that rage—they rage like the raging sea! Woe to the peoples who roar—they roar like the roaring of great waters! (Isaiah 17:12)
Then you will look and be radiant, your heart will throb and swell with joy; the wealth on the seas will be brought to you, to you the riches of the nations will come. (Isaiah 60:5)
“Who is this that rises like the Nile, like rivers of surging waters? Egypt rises like the Nile, like rivers of surging waters. She says, ‘I will rise and cover the earth; I will destroy cities and their people.’ (Jeremiah 46:7-8)
This is the word of the Lord that came to Jeremiah the prophet concerning the Philistines before Pharaoh attacked Gaza: This is what the Lord says: “See how the waters are rising in the north; they will become an overflowing torrent. They will overflow the land and everything in it, the towns and those who live in them. The people will cry out; all who dwell in the land will wail (Jeremiah 47:1-2)
The Lord will destroy Babylon; he will silence her noisy din. Waves of enemies will rage like great waters; the roar of their voices will resound. A destroyer will come against Babylon; her warriors will be captured, and their bows will be broken. (Jeremiah 51:55-56)
[T]herefore this is what the Sovereign Lord says: I am against you, Tyre, and I will bring many nations against you, like the sea casting up its waves. (Ezekiel 26:3)
As illustrated in some of the quotes above, this imagery also extends to related words like flood. In Isaiah 8:7-8 the coming of the Assyrian army to Israel is pictured as the mighty Euphrates overflowing its banks: “Therefore the Lord is about to bring against them the mighty floodwaters of the Euphrates—the king of Assyria with all his pomp. It will overflow all its channels, run over all its banks and sweep on into Judah, swirling over it, passing through it and reaching up to the neck.” Similar symbolism is found in Daniel 11:10 and Daniel 11:40:
His sons will prepare for war and assemble a great army, which will sweep on like an irresistible flood and carry the battle as far as his fortress. (Daniel 11:10)
At the time of the end the king of the South will engage him in battle, and the king of the North will storm out against him with chariots and cavalry and a great fleet of ships. He will invade many countries and sweep through them like a flood. (Daniel11:40)
The same imagery is also found in Nahum 1:8: “[B]ut with an overwhelming flood he will make an end of Nineveh.” The flood of Nahum 1:8 represents the allied armies of the Babylonians, Susianans, Scythians and Medes that destroyed Nineveh in 612 B.C. The same meaning is also implicit in Joel 2:9. Here an invading army is pictured breaking through a city like a surge of flood waters: “They rush upon the city; they run along the wall. They climb into the houses; like thieves they enter through the windows.”
The fact that sea represent foreign nations is not just limited to the Bible, this meaning is also found in the Talmud and the Dead Sea Scrolls. In the Talmud foreign nations are literally called “provinces of the sea.”1 Hymn 7 of the Dead Sea Scrolls depicts a foreign besieging army in flood or water imagery: “And I said Mighty men have pitched their camps against me with all their weapons of war. . . . The clamour of their shouting is like the bellowing of many waters, like a storm of destruction devouring a multitude of men; as their waves rear up[.]” Furthermore, in 1QpNah 1:3-4 of the Dead Sea Scrolls the sea in Nahum 1:4 is interpreted to represent the Kittim, the Romans: “’the sea’ is all the Ki[ttim . . .].”2 Above are a few examples in which sea, waters and flood represents foreign nations. But there is more to this symbolism. As stated above, aquatic imagery often denotes foreign kingdoms. However, there is an added layer of depth to this aquatic language that extends even to the word Abyss, a word often used as a name for the afterlife realm of the dead. For an explanation of the poetic link between foreign armies and the Abyss, the afterlife realm of the dead, see The Poetic Biblical Link Between “Sea” and “Abyss”.