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21 And God created great whales, and every living creature that moveth, which the waters brought forth abundantly, after their kind, and every winged fowl after his kind: and God saw that it was good.
6 By the word of the LORD were the heavens made; and all the host of them by the breath of his mouth.
'Three' denotes fullness, and 'a third,' not full.
(References: Arcana Coelestia 2788 [1-13])