I have found many Christians do not fully understand what Jesus Christ provided for them when He died on their behalf. They understand that Jesus made it possible for them to receive eternal life but only in the next life hence they continue to live on in this life as they did before. Whilst they may have read that Jesus said, I must go so that our Heavenly Father can send the third person of the Trinity, the Holy Spirit to indwell our Spirit and enable us to live the Christian life, they are quenching His work in their life (1 Thessalonians 5:19) and grieving Him (Ephesians 4:30).
“The spirit of man is the lamp of the Lord, searching all his innermost parts.” Proverbs 20:27
Note that the spirit of man is the lamp of the Lord. A lamp requires oil/Holy Spirit to function as God intended. When Adam and Eve disobeyed God, the Holy Spirit departed their spirit immediately. They died spiritually then and died physically 900+ years later.
Jesus made it possible for our Heavenly Father to empower us and to produce the fruit of the Spirit in our lives: love, joy, peace, patience, faithfulness, gentleness, goodness, kindness, and self-control. The Holy Spirit also provides the gifts of the Spirit for ministry:

The Hope we have and the Power we have does not disappoint, why?
“Not only that (having the peace of God), but we rejoice in our sufferings, knowing that suffering produces endurance, and endurance produces character, and character produces hope, and hope does not put us to shame, because God’s love has been poured into our hearts through the Holy Spirit who has been given to us.” Romans: 5:3-5
The Holy Spirit assures us of the Future Glory – Romans 8:18-30
“And not only the creation, but we ourselves, who have the first fruits of the Spirit, groan inwardly as we wait eagerly for adoption as sons, the redemption of our bodies.” Romans 8:23
“Likewise the Spirit helps us in our weakness. For we do not know what to pray for as we ought, but the Spirit himself intercedes for us with groanings too deep for words. And he who searches hearts knows what is the mind of the Spirit because the Spirit intercedes for the saints according to the will of God.” Romans 8:26-27
The Holy Spirit assures us of Final Victory – Romans 8:31-39
“For I am sure that neither death nor life, nor angels nor rulers, nor things present nor things to come, nor powers, nor height nor depth, nor anything else in all creation, will be able to separate us from the love of God in Christ Jesus our Lord.” Romans 8:38-39
