Arcana Coelestia #61
61. Everything that has to do with cognitions of faith is called spiritual, and everything that has to do with love to the Lord and towards the neighbour is called celestial. The former belong to man's understanding, the latter to his will.
Matthew 19:4-6
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He answered, "Haven't you read that he who made them from the beginning made them male and female,
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and said, 'For this cause a man shall leave his father and mother, and shall join to his wife; and the two shall become one flesh?'
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So that they are no more two, but one flesh. What therefore God has joined together, don't let man tear apart."