God expects that, when we accept Jesus Christ as our Lord and Savior, we will be radically changed.
In Romans 12:2 he tells us, "Do not conform any longer to the pattern of this world, but be transformed (metamorphoo) by the renewing of your minds." This transformation is to be a metamorphosis, of a magnitude at least comparable to that by which a caterpillar becomes a butterfly. He expects us to become totally different.
Scripture uses many different images to express the change that should occur:
We become "a new creation; the old has gone, the new has come" (2 Cor 5:17). It is almost as if we become a new species. Scripture speaks of the "first Adam" who was earthly and fell into sin, and the "second Adam" (Jesus Christ) who was sinless and holy (Rom 5:12-19; 1 Cor 15:44-49).
We are "made new in the attitude of your minds" (Eph 4:23).
We "put off your old self" and "put on the new self" (Eph 4:22,24; Col 3:9-10).
We "live by the Spirit" and not by the flesh (Gal 5:16; Rom 8:13).
We become "instruments of righteousness" rather than "instruments of wickedness" (Rom 6:13).
We have "been buried with him through baptism into death" in order that "we may live a new life" (Rom 6:4).
"I have been crucified with Christ and I no longer live, but Christ lives in me" (Gal 2:20).
We have "been set free from sin and have become slaves to God" (Rom 6:22). We are no longer "slaves to sin, which leads to death", but have become "slaves to ... obedience, which leads to righteousness" (Rom 6:16).
We are rescued ("translated" KJV) from the kingdom of darkness into the Kingdom of God's son (Col. 1:13). Our citizenship and our allegiance has been changed.
We have become adopted sons of God (John 1:12-13; Rom 8:15-16).
We are "born again" (John 3:3,5); born from above, of the spirit and not the flesh.
Each of these metaphors, in a different way, emphasizes the magnitude of the change that is expected. Each is dramatic and astonishing in itself; their cumulative effect is even more powerful. We are talking about a tremendous transformation. It should be visible to others, but its internal effect should be far greater than what others can perceive.
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