Look at the heart, and you will see something very interesting. Most people cannot stand a silent introspection because in the heart we see all kinds of wicked thoughts and behaviors. We depend upon ourselves for almost everything, we love ourselves as the greatest good, we cater to ourselves as if we were the highest lords, we seek our own ends as if we were the last of anything that mattered. We are sorely without hope to sing songs to our Jesus, for we are out of tune.
Yet if Christ has called us into His glorious reality, these same self-desiring hearts have become what theologians refer to as “regenerated.” They have been set straight and right and, according to Scripture, this renovation of the heart has been remade in the image of God. Because of this, our dependency upon ourselves is replaced by faith in God and trusting in His provision and sovereignty; our great love for ourselves has been replaced by a love for God and for His glory in our lives; our catering to ourselves, our wills that we demand over everything, have been subjected to a desire for obedience to the will of God; and finally, our self-seeking ends have been replaced by a self-denial and picking up our crosses to follow Christ.
Isn’t that a beautiful thing? What sin had destroyed, grace has renewed and restored. John Flavel writes what it means then, to now keep the heart: it is that “which is nothing but the constant care and diligence of such a renewed man to preserve his soul in that holy frame to which grace has raised it.”
The powerful point is this: Even though grace has renewed our hearts and brought them from stone to flesh, and even though we now desire the glory of Christ above ourselves, sin can actually come in and decompose it. Sin is uglier than we could imagine, more powerful than Satan himself, and like even the hardest of rocks, gets warped over time due to the elements of this world. It means that, though we want to sing to Christ in purity, we are like a musical instrument that though it is tuned perfectly for Sundays to play in the worship band, something small brings it out of tune again. That something small is the least bit of sin. And like that instrument that needs to be put back into tune again before it can play its sweet melody, our hearts too must be put back into tune again.
Isn’t this repentance? Isn’t this one of our great duties in keeping our hearts? Each day, each new morning, can’t we tune our hearts in repentance and see the great value and importance of it? Too many Christians go day in and day out amongst their lives without a thought towards repentance. Is it any wonder than, why the melody of our hearts can be so ugly sometimes? Is it any wonder why the world thinks our choir is more like a resounding gong, than a sacrifice of praise to our King?
We have been regenerated; shouldn’t we then take seriously the charge to keep our hearts and be broken and contrite before the Lord?