The conflicting natures of fallen Adam and risen Christ are well documented in the Scriptures. The nature of "the natural man" whose wisdom and lofty ideas blind him to the "foolishness of the gospel" as opposed to "the spiritual man" who, though "not wise, not mighty, not noble," has been favored above the wise and strong (see 1st Corinthians 1:26-29).

Paul's description of God's choice of the weak and the ordinary over the strong and noble in no way conflicts with the Lord's command to think on good things, to have our minds renewed through God's word, and to judge righteously.

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...a natural man does not accept the things of the Spirit of God, for they are foolishness to him, and he cannot understand them because they are spiritually appraised (1st Corinthians 2:14 NASB).

There is no justification Scripturally for efforts to "integrate" the fallen, corrupt nature of the old man with the new nature of the regenerate! God's solution is not integration, but deliverance through the Cross (putting the old to death with Christ) and the resurrection (bringing to life the new in Christ). The full and final solution is yet to come:

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For we know that the whole creation groans and suffers the pains of childbirth together until now. And not only this, but we ourselves, having the first fruits of the Spirit ... groan within ourselves, waiting eagerly for our adoption as sons, the redemption of our body (Romans 8:22-23 NASB, italics mine).

-Robin