As we can see from the creation of man in Genesis 2:7 where God formed the body from the "dust of the ground" and "breathed into his nostrils the breath of life (Spirit) and man become a living Soul." It is here that you see all three part distinguished at creation. The body is temporal (temporary) , but the Soul and Spirit do not end when the body dies. Each of us will live in eternity. It only a question of where we we spend that eternity. Some religions believe that our souls and spirit recycles over and over allowing us many chances to get it right, but that is contrary to the Bible says that there is one chance at life and then the judgment. (Hebrew 9:27)
From our projected chart, it seems that the faculty of the Spirit is one of eight faculties of a system call our Soul. The faculty of the Spirit is however inactive or dormant until it receives an endowment from God of His spirit that makes it lively. Imagine a parent helping their child open a bank account by signing up at the bank.
Okay, now you have a bank account, but no money. That bank account is literally worthless. The child has no money to put in the bank because he has no job. He asks his father, "But, Dad, I'm broke and I can't put anything in the account." Out of love for his child, the father puts $10 in the account and says, "I'll put more money in the account as part of your allowance."
When we become the child of God, He puts a deposit of His spirit into the empty faculty of our Spirit. It is now functional, and He also promise to keep adding to the replenishment of His spirit as a provision for any believer who wishes to walk by fatih and in His spirit.
But there is so much more to this amazing infusion of the Spirit. The faculty of the Spirit is one of two major influences throughout the other faculties of the Soul. The faculty of the Flesh is the other major influencing source. Which will control? It depends on which one we feed and favor. It is at this point that the other system of the Inner Man comes into play. The Heart like a river that waters the Soul supplying nutrients as it were a diet. Like the diet you feed your body, the nutrition from the Heart can help or hinder your spiritual growth.