Firmament
The firmament of heaven represents mutual love. The firmament, as in Genesis 1, signifies the internal man.
(References: Arcana Coelestia 24)
John 1:12-13
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But as many as received him, to them he gave the right to become God's children, to those who believe in his name:
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who were born not of blood, nor of the will of the flesh, nor of the will of man, but of God.