'Isaac' signifies the Lord's interior self and His divine rational in reference to divine good.

(Reference: Arcana Coelestia 1025, Genesis 17:19)

1024. That 'with you' means a regenerate spiritual person is clear from what has been stated frequently already; that is to say, 'Noah and his sons' means the spiritual Church which came after the Most Ancient, which was celestial. And because it means the Church, it means each member of the Church, and so a regenerate spiritual person.