My wife pointed out to me the other day something profound. The breath, she said, is essentially the border between the conscious will and the unconscious, automatic processes governing the human body. The heart, for example, beats at whatever rate it's supposed to. The stomach gets to work whether you tell it to or not. On the other hand, most things we control consciously do very little automatically. We choose to walk around; it is extremely rare for someone to start walking in their sleep. As for our mental life, well, it is true that we may have both conscious and subconscious thoughts, but how they interact is a complete mystery to me; in my common sense experience of the world, my thoughts are purely conscious.
But the breath is in between. On the one hand, I don't need to consciously think about breathing. When I sleep, my body automatically breathes. Even when I don't sleep, my lungs will automatically work at the pace they need to when the occasion calls for it. Yet I can choose to override these automatic rhythms. I can hold my breath. I can choose to breathe more slowly, or more quickly if I so desire.
This is especially evident in that most human of all activities: speech. To speak, I must take a breath big enough to finish the phrase I have in mind. This act of will is taken to a higher level in song.
In the Bible, "spirit" means "breath" or "wind." As far as I know, this is true in both Hebrew and Greek, both Old and New Testaments.
The Spirit of God, then, might be seen as the will of God coming to life in the physical world. As God prepares to speak, He takes a breath... and the Word that comes out will not fall to the ground without accomplishing its purpose. God is a good speaker, a well-trained singer.
The traditional Christian Trinity is recited as "Father, Son, and Holy Spirit," but one could make the case that "Father, Spirit, Son" is also an appropriate order. The Son is the Word, and the Word comes from the Father through His Spirit, that is, His Breath. Do we not say that the Son was conceived by the Holy Spirit? And if the Son is God Incarnate, that is, the Will of God made into a body, then is not the Spirit of God, so to speak, the boundary between God and His body? But I am stretching the image rather far; I don't mean to invent new theories, only jot down hypotheses.
For us, I think rediscovering the breath as spirit is important for our lives. When we focus on the breath as the center of our being, we reconnect the spiritual with the physical. We reconnect the human will with the human animal.
Sit and concentrate on your breathing. Sit up straight, fix your posture so that you have plenty of room to take in the air. Breathe slowly, so that you can enjoy it. As you breathe, you will notice that the rest of your body responds. Your heart changes its rhythm in response to the breath. You will feel the blood flow through all parts of your body and be made more aware of them. You will come into contact with your body on a physical level which is not habitual. On the other hand, you will also be more spiritually alert. The breath is an act of the will; it is a striving toward truth, toward beauty, toward the good. As you straighten out your back and breathe deeply, you will be reminded that your body is a sanctuary for the divine, a building that reaches upward.