The natural tendency is this. Formerly I used to use my mind to pore over history, over business, over chemistry, over questions of the world, or literature, or poetry. I used my keen mind to get the best out of those studies. But now my desire has been changed, so henceforth I employ the same mind in just the same way in the things of God. I have therefore changed my subject of interest, but I have not changed my method of working. That is the whole point. My interests have been utterly changed (praise God for that!), but now I utilize the same power to study Corinthians and Ephesians that I used before to study history and geography. But that power is not of the new creation; and God will not be satisfied with this simple exchange of interests. The trouble with so many of us is that we have changed the channel into which our energies are directed, but we have not changed the source of those energies…
Anything we can do without prayer and without an utter dependence upon God must come from the spring of natural life that is tainted with the flesh… Whether naturally gifted or not… they must know the touch of the Cross in death upon all that is of nature, and their complete dependence upon the God of resurrection…
Every plant which my heavenly Father planted not, shall be rooted up (Matt 15:13)… God is the only legitimate Originator in the universe (Gen 1:1)….
Origin determines destination, and what was ‘of the flesh’ originally will never be made spiritual by any amount of ‘improvement’.
The Normal Christian Life, Tyndale House, 1957/1977, 230-234