Association with angels comes about through the Word’s earthly or literal meaning because three levels of life have been built into every one of us from creation; a heavenly level, a spiritual level, and an earthly level. As long as we are alive in the world we are conscious of the earthly level; during this time we are conscious of the spiritual angelic level only to the extent that we have genuine truths, and we are conscious of the heavenly level only to the extent that we live our lives by those truths. Even in that case, we do not come into full consciousness of what is spiritual or heavenly until after death, because what is spiritual and heavenly is locked and hidden inside our earthly ideas. When our earthly level passes away through death, the spiritual and heavenly levels remain and form the basis of the ideas in our thinking.
It stands to reason, then, that only the Word has spirit and life. As the Lord says:
The words that I speak to you are spirit and are life. (John 6:63)
The water that I will give you will become a fountain of water springing up to eternal life. (John 4:14)
People do not live on bread alone, but on every word that comes from the mouth of God. (Matthew 4:4)
Work for the food that remains for eternal life, which the Son of Humankind will give you. (John 6:27)
from True Christianity, Volume 1, Section 239