Arcana Coelestia #1020
1020. That these things are meant becomes clear from the fact that everything put together as history from Genesis 1 down to Eber in Chapter 11 means something different from what appears in the letter, and from the consideration that the historical narratives there are purely made-up history customary among the most ancient people. When attesting the truth of some matter they would say that 'Jehovah said it'. Here however 'God' is used because the subject is the spiritual Church. And they did the same when anything true was being, or had been, put into effect.
Sleep
In a general sense, sleeping in the Bible represents a state of obscurity about spiritual matters, a state in which you are not recognizing things that are spiritually true and not seeking what is spiritually good. In particular -- especially when someone is in a "deep sleep" -- it represents a state in which we believe we think, feel and do everything from ourselves, without acknowledging that all life comes from the Lord.
(References: Arcana Coelestia 147, 150, 3715, 5210)