In Genesis 2:24, this signifies to separate from the internal man. (Arcana Coelestia 160)

In Genesis 44:22, this signifies to separate truth from spiritual good, which cannot be done, or else the church perishes. (Arcana Coelestia 5812-5813)

In Genesis 50:8, this signifies that the goods of innocence and charity, interior and exterior, remained in the inmost parts of man. (Arcana Coelestia 6532)

160. Verse 24 Therefore a man (vir) will leave his father and his mother and will cling to his wife, and they will be one flesh.

'Leaving father and mother' is leaving the internal man, for the internal is that which conceives and gives birth to the external. 'Clinging to his wife' is in order that the internal man may be within the external. 'Being one flesh' means that they are there together. Previously the internal man, and the external man deriving from the internal, were spirit, but now they have become flesh. In this way celestial and spiritual life was joined on to the proprium in order that they might seemingly be one.