Air" in the Bible represents thought, but in a very general way – our capacity to perceive ideas and the way we tend to think, rather than our specific ideas about specific things. We see the world around us through the air, and seeing corresponds to understanding. We hear through the air, and hearing corresponds to being taught and obeying. Birds fly in the air, and they represent specific thoughts and ideas. And breathing itself – taking in air and passing oxygen to the blood – represents our understanding of true spiritual ideas.

In Genesis 1:26, when used with fowls or birds of the air refers to the air we breathe, but sky, or heavens where are stars, and together these terms refer to both the spiritual and natural man, and to their food, or goods and truths. (Arcana Coelestia 57, 58)

In Genesis 3:8, the only Old Testament reference to air is in the phrase "cool of the day" (at the time of the evening breeze) which signifies the period when the church still had some spiritual perception. (Arcana Coelestia 221)

In Revelation 9:2; 16:17, air signifies the divine truth, darkened by infernal falsities. (Apocalypse Explained 541, Apocalypse Revealed 423)

In Revelation 16:17, everyone in the spiritual world breathes air according to his faith. (Apocalypse Revealed 708, Apocalypse Explained 1012, Apocalypse Revealed 708)

The sun in the Bible represents the Lord, with its heat representing His love and its light representing His wisdom. “Daytime,” then, represents a state in which we are turned toward the Lord, receiving His love and being enlightened by His truth. And “nighttime,” obviously, represents states in which we are turned away from the Lord, left cold and blind to the truth. The most common word used for it in the New Christian theology is “obscurity.” The darkness is not absolute, of course. The light of the moon represents the understanding we can have based on facts and our own intelligence. But while the moon reflects some of the sun's light, it offers almost no heat, so this kind of understanding is a cold one, without the warmth of love. And at its darkest and coldest, night represents a state of judgment. This happens when a person -- or a church -- becomes so mired in evil and falsity that there is no light or heat. The Lord can then step in, separate the good from the evil, consign the evil to hell and begin rebuilding based on the remnant that is still good. Drastic as that sounds, it is something that we all go through repeatedly in various aspects of our loves, so that we can be rid of what is evil and let the Lord rebuild us as angels.