Just ran across this from Calvin. By “integrity” he doesn’t mean what we usually do (ethical consistency) but “singlemindedness”, the opposite of “doublemindedness”.
Let us set this before our eye as the end at which we ought constantly to aim. Let it be regarded as the goal towards which we are to run. For you cannot divide the matter with God, undertaking part of what his word enjoins, and omitting part at your own pleasure. For, in the first place, God uniformly recommends integrity as the principal part of his worship, meaning by integrity real singleness of mind, devoid of gloss and fiction, and to this is opposed a double mind; as if it had been said, that the spiritual commencement of a good life is when the internal affections are sincerely devoted to God, in the cultivation of holiness and justice.
But seeing that, in this earthly prison of the body, no man is supplied with strength sufficient to hasten in his course with due alacrity, while the greater number are so oppressed with weakness, that hesitating, and halting, and even crawling on the ground, they make little progress, let every one of us go as far as his humble ability enables him, and prosecute the journey once begun. No one will travel so badly as not daily to make some degree of progress. This, therefore, let us never cease to do, that we may daily advance in the way of the Lord…
Calvin, Institutes of the Christian Religion 3.6.5
Don’t critique Calvin before reading a bit of his writings! The reader can listen to the Institutes as audible files from librivox.org.
We might also add this from Wolfgang Schrage concerning how the wretched man of Romans 7 is a thing of the past for the Christian:
The human contradiction…the dichotomy and division within the self, is a thing of the past. The radical nature of this new being implies an undivided integrity of God’s claim upon us.
From The Ethics of the New Testament [Philadelphia: Fortress, 1988], 187; see also my “Are you a wretched man or woman? Should you be?”
“Sanctification as singlemindedness,” by Gary S. Shogren, Professor at Seminario ESEPA, San José, Costa Rica
Open Our Eyes, Lord! 