Spreading themselves
'Spreading themselves on the earth,' as in Genesis 8:17, signifies the internal self operating on the external.
(References: Arcana Coelestia 913)
Arcana Coelestia #7
7. The first state is the state which precedes, both the state existing from earliest childhood onwards and that existing immediately before regeneration; and it is called a void, emptiness, and thick darkness. And the first movement, which is the Lord's mercy, is 'the Spirit of God hovering over the face 1 of the waters'.
Footnotes:
1. literally, The faces