The flood described in Gilgamesh and the one described in described in the old testament are similar, but also unique in their own ways. In the flood described by Gilgamesh, several gods ordered the flood to destroy all the people because of the sins they committed. But similar to Noah, one man had a dream that told him to build a boat and gather all the animals and load them on board. Another similarity is that they both found refuge on the top of a mountain. One difference is that Noah's Flood lasted for 40 days, and Gilgamesh's flood only lasted 6 days. In both stories, the god and gods were mostly okay with the specific people surviving the massive flood because they were truly good people and deserved to continue to live.
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