Paul is clear that the ability to put off (repent of and stop doing) sin and putting on (embracing and habitually doing) righteousness is the result of allowing the Holy Spirit to renew our minds through the taking in of Scripture. A changed life comes from a renewed mind.
The key is alertness of mind and attentiveness to Scripture. Some other writers from other generations have noted this same truth and the danger of being inattentive to our minds and Scripture:
I believe a very large majority of churchgoers are merely unthinking, slumbering worshippers of an unknown God. [Charles Spurgeon]
Whatever really shapes a man’s thinking his life [actions]. [Derek Kidner]
We are only poor for this reason, that we do not know our riches in Christ. In time of temptation, believe Christ rather than the devil. Believe truth from truth itself. Hearken not to a liar, an enemy and a murderer. [Richard Sibbes]
Words of Grace 