In Section 8 I showed that the oneness of God is written into each human mind at the deepest level, since it is central to all things that flow from God into our souls. It has not yet come down from there into our intellect, however, because we have been lacking concepts we need in order to go up toward God. Each of us needs to make a pathway for God [Isaiah 40:3], meaning we need to prepare ourselves to receive God, and this preparation requires certain concepts.
The concepts we have been lacking are listed below. Their lack has deprived our intellect of the penetration to see that there is one God, that there can be only one underlying divine reality, and that all things in the material world come from that underlying reality.
(a) Until now, no one has known anything about the spiritual world, where there are spirits and angels and where we go after we die.
(b) The spiritual world has a sun that is pure love from Jehovah God, who is within that sun.
(c) The heat from that sun is essentially love, and its light is essentially wisdom.
(d) As a result, everything in that world is spiritual and affects us in our inner selves, forming our will and our intellect at that level.
(e) By means of that sun, Jehovah God produced not only the spiritual world and all the countless spiritual things in it, which are substantial, but also the material world and all the countless material things in it, which are physical.
(f) Until now, no one has known the difference between “spiritual” and “earthly,” or even what “spiritual” essentially means.
(g) No one has known that there are three levels of love and wisdom that have been used to structure the angelic heavens.
(h) No one has known that the human mind is differentiated into the same number of levels so that we can be lifted to one of the three heavens after death, depending on our life and faith.
(i) Lastly, none of the above would be the case for one instant were it not for the underlying divine reality—the Absolute in itself; the First and the Beginning from which all things exist.
Even though these are the concepts we need in order to go higher and recognize the divine reality, they have been lacking until now.
I say that we go higher, but I really mean that we are taken up by God. We have free will; we can use it to gain religious knowledge. When we exercise our intellect and gain religious knowledge from the Word, we smooth a pathway that God can use to come down and lift us up.
The concepts that can lift our intellect higher, and let God take us by the hand and lead us, can be compared to the steps on the ladder that Jacob saw. It was set up on the ground but the top of it stretched into heaven. Angels were climbing up on it and Jehovah was standing above it (Genesis 28:12–13).
When we lack these concepts or reject them with contempt, the situation is quite the opposite. Under these conditions, the reach of our intellect can be compared to a ladder on the grounds of a magnificent mansion, but the ladder extends only to a window on the first floor, where people are staying, and does not reach the windows of the second floor where there are spirits, let alone the windows of the third floor, where there are angels.
If we lack or reject these concepts, we are limited to the atmospheres and matter in nature that we experience with our eyes, ears, and noses. From these sources we get only atmospheric and material ideas about heaven and about God’s underlying reality and essence. Thinking on the basis of them, we will never decide anything about whether God exists or not, or whether there is one God or many, much less what the underlying reality and essence of God are like. As a result, in ancient times, and nowadays as well, people have come to believe in a plurality of gods.
from True Christianity, Volume 1, Section 24