In the words of St.Athanasius;
"God became man so that man shall become god."
And Jesus said;
"I am the Way the Truth and the Life." (John14:6)
Answer:
The "spirit" that Jesus commended is the spirit of His human soul that has a God given "freewill & intellect"and not the Holy Spirit as the Holy Spirit in the bible will be sent proceeding from Jesus and God the Father after His Ascension.That human spirit meant to Glorified God by the action of the "freewill & intellect" bestowed on every soul created by God. Jesus is a God-Man, Truly God & Truly Man, created with a rational soul and human will.So,when the physical body suffers death the rational soul must return to God.
The Holy Spirit the Spirit of Christ which dwells fully in his human spirit
in a mystical way called "hypostatic union". The Most Holy Trinity is inseparable according St.Vincent Ferrer and Church Teaching.(Will of the Father,Holy Spirit,Jesus)
Jesus Incarnate as the Logos, is empowered by the Holy Spirit in doing the Will of the Father.
After Jesus death, the sending of the Holy Spirit mission is to dwell in each redeemed soul to imitate the Life of Jesus Christ in His assumed humanity.
Douay-Rheims Bible
But the Paraclete, the Holy Ghost, whom the Father will send in my name, he >will teach you all things, and bring all things to your mind, whatsoever I >shall have said to you.
(John14:26)
Jesus humanity follows perfectly and completely the Will of the Father as Jesus said in John6:38,
John 6:38 King James Version (KJV)
"For I came down from heaven, not to do mine own will, but the will of him >that sent me."
Jesus came down and assumed the form of human to show us that we need to accept,embrace and follow the Will of the Father in our lives by the power of the Holy Spirit dwelling in each of everyone ofus..
So that at the end of our faith journey here on earth we can say to the ABBA Father, my mission is finished "into your hands I now commend my spirit".
Jesus had shown us the Perfect Way of Living our God-given faith.God has given us a life with body & soul to share in His divine life in the end and we must perfect our faith journey here on earth like Jesus in perfect obedience to the Will of the Father. In the end of our life we must reach the Theosis as we called it divination according to Church Father's teaching.
"Be perfect/holy, therefore, as your Heavenly Father is perfect/holy."
(Matthew5:48).
As Jesus clearly pointed to us who are the ones that can enter in God's Kingdom in the gospel.
"Not everyone who says to Me, ‘Lord, Lord,’ will enter the kingdom of heaven, >but only he who does the will of My Father in heaven." (Matthew7:21)
In closing, I 'd like to quote St.Augustine words,
The Glory of God is man FULLY ALIVE!.
or in the very words of Jesus Christ.
I have come to give them life and have it to the FULL! (John10:10)
So, the human was given by God a body and soul with freewill and intellect. But in order for the soul to animate the body the soul must be alive in the spirit.
This spirit is coming from God as He breathe it to Adam for it to become a living soul.
This living soul empower by the spirit coming from God imprinted in his soul his God given mission.
The human soul must activate or animate his body with the power of his spirit to acquire all the graces comimg from the merits of Christ entrusted to the Church.
And at the end of life journey this spirit of man return to God united to his soul for judgement.
This is why a man sentenced to hell by his own freewill manifested in his evil actions on earth is condemned to hell with his soul but the spirit that was breathe in him originally return to its maker.
The body return to earth as dust.
The spirit return to God.
The good soul goes to heaven with his spirit while the bad soul goes to hell with his God given spirit separated and return to God. Only his soul is eternally punished in hell because the God given or breathe-in spirit is the goodness or light of God and must all return to its maker.
Godbless!