We also have to take in account that people back then doesn't know much about the brain. they try to explain it the best they can. we know that they understand that mind is part of the body- body cannot function without the mind. Paul talks about renewing our minds changing who we are. scriptures always said. Whoever thinks in his heart, so is he... Heart equals mind. there's many other scriptures that seems to point to the mind as well. Once the mind is active, it brings body to life.
Job 7:11 seems to indicate that the spirit and soul to mean pretty much the same thing. "Therefore I will not refrain my mouth; I will speak in the anguish of my spirit; I will complain in the bitterness of my soul." This indicates the mind and moral conscience and emotions and so on. It seems to point to the seat of the mind.
"For the word of God is quick, and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart." (Heb 4:12)
I think that even this passage is saying that, at least in a living person, there is hardly a distinction between the two. It seems to point to the "mind." the seat of emotions, conscience, moral conscience, awareness of life, etc.
The body cannot function without the mind. when the Mind is separated from the body, the body dies. the same goes with brain damage. Once the mind is damaged, the body cannot function properly. There's thousands of mental disorders that we know about. The Mind/Body relationship is important.
I think whenever they use the word Soul, they refer to the whole you, who you are as a whole, the whole you. the whole Mind that refer to who you are. You are whoever you are.. for example. I am Denise. My soul's name is Denise. Denise is the whole soul- the whole mind that makes up Denise as she is. I know who i am.. This is my life that is part of this body. My mind makes me who I am as a whole.
The spirit is the life of the man. Their identity.
So- here's a thought to consider
Father, into your hands I commit my life- my whole me or My identity- my essence, My mind, my life force that is part of me. my spark that makes me who I am. whatever it really means to refer to my whole self. that creates who I am as a person. you get the idea.
Just my two cents. Hope it helps.