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18 And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.
6 Whoso sheddeth man's blood, by man shall his blood be shed: for in the image of God made he man.
The firmament of heaven represents mutual love. The firmament, as in Genesis 1, signifies the internal man.
(References: Arcana Coelestia 24)