Romans 12:2: And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.
Romans 12:1 begin with familiar and famous words. “I urge you . . . in view of God’s mercy, to offer your bodies as living sacrifices, holy and pleasing to God—which is your spiritual worship.”
We can never have a true Christian relationship with others until we are fully committed to God.
Transformation comes from deep knowledge of the Word of God and fellowship with Christ. With transformation, our hearts and minds become renewed into the image of God.
Paul entreats those who follow Christ - by the mercies of God, to present their bodies as a living sacrifice to Him. This is a powerful appeal. We receive from the Lord every day the fruits of his mercy. It is expected of us to give to God: a reasonable service, which we are able to give.
When we become converted, we take on sanctification. This causes us to be set apart for God. The Word of God causes a renewing of the mind; a change, not of the substance, but of the character of the soul.
The progress of sanctification, dying to sin more and more, and living to righteousness more and more, is the carrying on this renewing work, till it is perfected in glory. The great enemy to this renewal is conformity to this world.
It is the Holy Spirit who removes the “veil” or covering, from hearts and minds. The work of the Holy Spirit in the lives of Christians should be allowed to cause the transforming of the will, affections, and conversation, till there is a change of the whole man into the likeness of God, in knowledge, righteousness, and true holiness. Therefore, to be godly, is to give up ourselves.
God’s abiding presence comes in our lives through the Holy Spirit. The Holy Spirit leads Christians from justification through sanctification to glorification. As
believers manifest the fruit of the Spirit (Gal. 5:22-23), they are progressively being transformed into His likeness. “Christ likeness” is the goal of the Christian walk.
Transformation (Gk. metamorphoo) denotes character for the better (Romans 12:2) through the renewal of the thinking power. Paul considered it as a distinct operation of the Christian faith and compels Christians to prove in everything what is acceptable unto God(Eph. 5:10, Man, in his natural state, looks more to the point of how he may please men”.
In 2 Cor. 3:18, Paul speaks of the Christian’s being “transformed into the same image from glory to glory,” etc. In this passage the gospel is spoken of as a mirror, in which the glory of Christ gives itself to be seen; the Christian, studying the gospel, becomes so transformed that the same image which he sees in the “mirror”—the image of the glory of Christ—presents itself on him, i.e., he is so transformed that he becomes like the glorified Christ.
What the Bible is saying is that the believer must undergo a radical change within his inner being in order to escape the world and its doom. Man’s spirit must be in control of his mind. He must be transformed and changed inwardly. His real self—his very nature, essence, personality, inner being, his inner man—must be changed.
1 John 5:20 (He "hath given us an understanding, that we know him that is true") speaks in the same sense as in Romans 12:2, a renovated mind is one capable of knowing Christ.
We can look back to Christ’s Great Commandment rendered in Matthew 22:37—"Thou shall love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind (understanding). It can be related to "understanding enlightened from above" (2 Tim. 2:7 "The Lord gives thee understanding in all things").
Moral life proceeds from the heart and manifests itself without. The God-ward characteristic of man proceed from the heart, and is realized in the life through the will, which consecrates itself actively to the accomplishment of God’s will; and through the mind, which pursues the track of His thought in all His works.
No one can comprehend God (Romans 11:34), but through the guidance of the Holy Spirit, believers have insight into some of God’s plans, thoughts, and actions—they, in fact, have the “mind of Christ.” Through the Holy Spirit we can begin to know God’s thoughts, talk with him, and expect his answers to our prayers. Are you spending enough time with Christ to have his very mind in you? An intimate relationship with Christ comes only from spending time consistently in his presence and in his Word. Read Phil. 2:5ff for more on the mind of Christ.