When communicating the gospel to unbelievers, it is tempting to make conversion the end of the conversation. That is, it is possible to be so concerned about the salvation of the individual that we ignore what happens to the convert after his salvation decision.
But God cares about what happens to us after our salvation. It is not enough that we have been freed from God’s wrath; He also saved us so that we would experience freedom from sin’s power. In other words, sanctification is essential. Progress in our salvation matters. Sanctification is integral to salvation.
But that does not mean that the only thing that matters is external conduct. External conduct and a change of our activities is expected, but only as they derive from a change of heart and desire. As God demonstrated repeatedly in the Old Testament, He is far more concerned with the attitude of heart behind one’s actions than the actions themselves. So obedient sacrifices and worship are for naught if they are done with a heart that is far from God (e.g., Is. 29:13; 1 Sam. 15:22; Ps. 51:16; Amos 5:21-24).
This is why David Powlison has written:
The longings of the human heart must be changed if we are to become all that God designed us to be. Our longings are illegitimate masters; even where the object of a desire is a good thing, the status of the desire usurps God. Our cravings should be recognized in order that we may more richly know God as the Savior, Lover, and Converter of the human soul. God would have us long for Him more than we long for His gifts [or anything else].
Do activities that conform to the character of God — but only do them as they reveal the true desires of your heart. It is an evil to practice true actions from a heart that does not care for or desire God. So if you have no yearnings for God but are merely conforming your external life to some perceived standard of righteousness, then repent of your callousness and ask God to give you a renewed passion for and delight in Him (Ps. 51:10).
Words of Grace 