Paul tells us in Thessalonians to keep your soul, spirit, and body blameless until the coming of our Lord Jesus Christ.
1 Thessalonians 5:23 -
"And the very God of peace sanctify you wholly;
and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ."
Paul then says in Hebrews that our soul and our spirit can be divided asunder by the Word of God.
Hebrews 4:12 -
"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."
What this means is that when a person responds to the powerful message of God's Word by accepting Christ, their old spirit is cut away from their soul and is then replaced with a new reborn spirit (i.e. they are born again spiritually into God's Kingdom).
So we have three distinct parts that all function as one just as God has three distinct parts to Him that function as one.
Soul = Makes the ultimate decisions.
Body = Earthly body that can influence you into fleshy or worldly matters.
Spirit body = Spiritual body that can influence you into spiritual matters.
The soul, body, and spirit all function as one living human being in perfect harmony.
Father = Greater than the Son & has given commands to the Son.
Word = The Word became flesh in the man named Jesus.
Holy Spirit = The Comforter is the Spirit of God that is given to true believers.
The Father, the Word, and the Holy Spirit all function as one God in perfect harmony.