To be behind, (Genesis 18:10), signifies not to be joined together, but at his back. What is separated from any one, this is represented in another life, by a kind of rejection, as it were, to the back. (Arcana Coelestia 2196)

In Genesis 19:17, this signifies being away from doctrinal things. (Arcana Coelestia 2417)

In Genesis 16:13, Here, behind, or after, signifies within or above, or an interior or superior principle.

In Revelation 1:10, 'behind' signifies that people who do not approach the Lord only (Apocalypse Revealed 42)

(Reference: Arcana Coelestia 1955)

2195. 'And Sarah heard it at the tent door' means rational truth at that time close to holiness. ]his is clear from the representation of 'Sarah' as rational truth, dealt with in 2173, 2174, and also from the meaning of 'a tent' as holiness, dealt with in 414, 1102, 1566, 2145, and so from the meaning of 'tent door' as the entrance to holiness, and thus close to holiness, dealt with above in 2145. The implications of these matters follow next.