Arcana Coelestia #35
35. Man has two inherent powers of will and understanding. When the understanding is governed by the will they then constitute one mind and so one life; for what a person in that case wills and does he also thinks and intends. But when the understanding is at variance with the will, as it is with people who claim to have faith and yet live otherwise, then a mind previously one is split in two. One half seeks to transport itself into heaven, while the other inclines towards hell. And because the will is what accomplishes everything, the whole man would rush straight into hell unless the Lord took pity on him.
Genesis 1:6-8
6
And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.
7
And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so.
8
And God called the firmament Heaven. And the evening and the morning were the second day.