Arcana Coelestia #1855
1855. Verse 16. And in the fourth generation they shall return hither, for the iniquity of the Amorites is not yet consummated. “In the fourth generation they shall return hither,” signifies the time and state of restoration; “for the iniquity of the Amorites is not yet consummated,” signifies the last time, when there is no longer any good.
Genesis 15:16
16
In the fourth generation they will come here again, for the iniquity of the Amorite is not yet full."