The Bible is clear: the Genesis flood covered the entire earth (Genesis 7:19-20). Every living person and land animal died in a global deluge except those in the ark (Genesis 7:21-22). Even God's promise to never flood the earth again spoke to its extent: "… never again shall all flesh be cut off by the waters of the flood, and never again shall there be a flood to destroy the earth" (Genesis 9:11).
Was the Noahic flood global?
The idea that the Genesis flood was local rather than global may have begun in the 16th century in an informal think tank in colonial America. They observed that some of the Native American tribes they'd had contact with did not have a flood mythology. The speculated reason was that the natives must have pre-dated the flood, which would mean the flood did not reach the western hemisphere. In fact, they posited, it was possible that the natives pre-dated even Adam. The idea took hold among London's thinkers, and certainly informed the racist undertones of Darwinian evolution. Ironically, the entire idea is uninformed. The Aztecs, Ojibwes, Delawares, and Incas all have flood mythologies, some specific enough to say that the original creation lasted for 1716 years, the Creator told a righteous man to build a boat, and the survivors lived by floating on a log with a few animals. The Aztecs even mention that the man knew the waters had receded when a dove did not return.
The mythologies about a global flood may be one of the greatest secular proofs that the event was worldwide. Tribes in Tanzania, China, India, Indonesia, Wales, Siberia, the Andaman Islands, as well as the Australian Aborigines and the Maasai in Africa all have stories of a great flood that the Creator used to discipline disobedient people. Atheists speculate the stories were inspired by the appearance of seashell fossils high in mountain ranges or local flooding caused by the sudden melt of glaciers. But this doesn't explain the universality of the stories or the frequently found similarities.
A global flood also explains many of the geological features we see today. Sea fossils are found throughout the world at every elevation—consistent with rising waters covering the earth. Layers of rock formation in the Grand Canyon show evidence that several strata were bent and curved while still warm enough to fold without cracking. The shape of the sea floor shows signs of catastrophic geological violence. And even the stories of the gardens of Babylon can be explained by a global flood; the geological pyrotechnics on the ocean floor would have heated the water in the Arabian Sea, causing hypercyclones that would have sent rain over Saudi Arabia, Pakistan, Afghanistan, Iran, and even Egypt. As time passed and the waters cooled, the storms decreased and the Middle East became a desert.
Bible references match these evidences. Several passages mention the global flood survived by only eight people. Isaiah 54:9 refers to Noah's floodwaters covering the earth. Hebrews 11:7 lauds Noah's faith as he built the ark. Most convincingly, Jesus mentions the flood in Matthew 24:38-39 and Luke 17:26-27. Peter not only talks about the eight people brought through the water (1 Peter 3:20), he warns that in the last days people will deny the flood, saying that "scoffers will come in the last days with scoffing … For they deliberately overlook this fact, that the heavens existed long ago, and the earth was formed out of water and through water by the word of God, and that by means of these the world that then existed was deluged with water and perished" (2 Peter 3:3, 5-6). Verse 7 goes on to explain why doubters will deny the flood—it reminds them too much of their own coming judgment.
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