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27 So God created man in his own image, in the image of God created he him; male and female created he them.
1 And God blessed Noah and his sons, and said unto them, Be fruitful, and multiply, and replenish the earth.
The firmament of heaven represents mutual love. The firmament, as in Genesis 1, signifies the internal man.
(References: Arcana Coelestia 24)