“Each of the ten plagues delivered upon Egypt corresponds to one of [the] ten ‘Ma’amarot’ -pronouncements – [which G-d used to create the world]… What is the meaning behind this correspondence?
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The Seror Ha’mor explains that the purpose was to show…that G-d created the world and exerts complete control and authority over it… Pharaoh and the Egyptians denied the existence of a single G-d who created the world, and so G-d proved them wrong by reversing the process of creation, undoing and then restoring each of the ten pronouncements with which the world came into existence.”