In any given thing there are general essential components and there are also specific essential components. The general and specific components combine to make one essence.
In our case, our general essential components are our soul, our body, and the things we do. These components combine to make one essence, as you can see from the fact that one component comes from and exists for the other in an unbroken chain. We begin from our soul. The soul is essence of semen that originates us. Our soul not only initiates but also sequentially produces the features of our body. Then there are things we do, which come from both our soul and our body. Because one of these components produce another, and therefore the subsequent components are grafted onto and connected to those that came before them, it follows that these three components share one essence. This is why they are called the three essential components.
from True Christianity, Volume 1, Section 166