2
And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.
Genesis 1:2
Gathered together, waters
In Exodus 15:8, this signifies falsities gathered together. Waters normally signify truths, but in this case, where they were blocking the escape of the Children of Israel from slavery and signify the opposite: falsities.
(References: Arcana Coelestia 8286)
Fruitful
To be fruitful relates to goodnesses, and to be multiplied, truths.
(References: Arcana Coelestia 1014, 1018)
