As we think about sin, the most obvious connection between sin and our nature is to the physical, biological side. This is the slavery Paul is discussing when he speaks of sin working through our bodily members. More OT, Isa. This is also true of human beings under the condition of sin. The natural motions of our lives produce mire and dirt.
Sin is a part of the internal structure of our lives.
We do not have to go out of our way to sin. We need only to do what comes naturally. No special effort is needed to produce sin in our lives. No wonder the biblical writers speak of how sin entraps us. In our duality, much a part of Hebrew view of the human experience, we are both spirit and physical, body and soul.