The kingdom of God is the true ecology of the human soul.
The acid test for any theology is this: Is the God presented one that can be loved, heart, soul, mind, and strength? ... If it fails to set a lovable God--a radiant, happy, friendly, accessible, and totally competent being--before ordinary people, we have gone wrong
The spirit is the part that is supposed to consciously direct everything in the person, including the soul.
The law of the Lord is perfect, restoring the soul.
We see that the soul is the deepest and the most vital part of the person as a whole. It is often treated as the person, and we actually do this when we talk about "saving our soul."
I do emphasize that we cannot just get out of the Bible a definition of the soul.
Now, of course, you have guidance devices and all sorts of things. The soul would be more like the way this is all hooked together, a system of coordination.
The soul's order is re-established in God through the law.
It's important to distinguish the soul from the spirit, or will, because the will or the heart or the spirit is the executive center of the self.
I would say the soul would be more than the engine. The soul would be like the computer system that coordinates everything, from the smog device to the fuel injection system to the brakes.