‘The duty of mortification is only accomplished through the Holy Spirit. He alone does the actual work.
First, the Holy Spirit clearly and fully convinces the heart of the evil and guilt that needs to be mortified. Without His conviction there would be no thorough work done. ‘He convinces of sin (Jn 16.8). He alone can do this. If mans rational ability could do so, we might see more conviction of sin in the world. But this light is not powerful nor reliable enough, as we have seen. Unless we are convinced of the unique power of the Holy Spirit, we shall go on living in futility about sin.
‘Second, The Holy Spirit alone reveals to us the fullness of Christ for our relief. It is this which will uphold the heart from false ways and from despondency.
Third, the Spirit alone establishes the heart in expectation of help from Christ. This is the great means of mortification as we have discovered in 2 Corinthians 1.20-22;
“For all the promises of God find their Yes in him. That is why it is through him that we utter our Amen to God for his glory. And it is God who establishes us with you in Christ, and has anointed us, and who has also put his seal on us and given us his Spirit in our hearts as a guarantee.”
“Sin is the despairing refusal to find your deepest identity
in your relationship and service to God. Sin is seeking to
become oneself, to get an identity apart from Him.”
Tim Keller, The Reason for God
Fourth, the Spirit alone brings the cross of Christ into our hearts with its sin-killing power. By the Spirit we are baptized into the death of Christ. By baptism we recognize the implantation of Christ’s life in our souls, replacing our old, sinful self. The apostle writes, “We know that our old self was crucified with him in order that the body of sin might be brought to nothing, so that we would no longer be enslaved to sin.” Romans 6.6
Fifth, the Spirit is the author and finisher of our sanctification. He provides the resources and new influences of grace for holiness and sanctification. He does this when the contrary principle of the flesh is weakened.
“For this reason I bow my knees before the Father, from whom every family in heaven and on earth is named, that according to the riches of his glory he may grant you to be strengthened with power through his Spirit in your inner being, so that Christ may dwell in your hearts through faith—that you, being rooted and grounded in love, may have strength to comprehend with all the saints what is the breadth and length and height and depth, and to know the love of Christ that surpasses knowledge, that you may be filled with all the fullness of God.” Ephesians 3.14-19
Finally, in all the soul’s relationships with God, we have the support of the Holy Spirit. Where else do we receive this power, life, and vigor of prayer? Where is our efficacy to prevail with God? Is it not from the Spirit? He is called ‘the Spirit of supplications,’ promised to those ‘who look on him whom they have pierced’ (Zech 12.10). It is the Spirit who ‘maketh intercession for us with groanings which cannot be uttered’ (Romans 8.26).
The Spirit is the great go-between and the way for faith to prevail with God.’
*”For if you live according to the flesh you will die, but if by the Spirit you put to death the deeds of the body, you will live.”