There are two kinds of duty: 1) Duty of the unbeliever; and 2) Duty of the believer. This can be illustrated by asking the question, “Why does the church goer attend worship service?”
Is it out of duty because it is good that the individual needs such encouragement and correction to be a good citizen of the great land of America? This motivation being the protective establishment of a system of government created to provide a shield and defense of freedoms to despicable, greedy, corrupt and morally reprehensible citizens and people who naturally seek power and wealth to the detriment of themselves and society.
Or is it out of duty because I (eternally dependent upon the Spirit) am crucifying the flesh, mortifying the deeds of my old man full of evil and vile desires, that I by means of grace, therein proving through test and trial, pain and suffering that God has gifted eternal life and He will by His promise grant me by His gracious generosity on that Day the fulfillment and euphoric completion of His divine gift secured in His Son, worked out by His Spirit?
The duty of the first and former being completed by devout men and women, ignorant of the Gospel of Jesus Christ, having only a distant, formal, cold and incompatible public knowledge of the power of God similar to the vile devils, and thereby being spiritually dead do pile up future agony upon themselves when on that Day they come to realize their work of religion fails the test of a mighty, awesome, perfect and holy God who has patiently endured their arrogance, and in that patience has actually blessed them with many common graces that He has poured generously and lavishly upon His creation, which they have rudely, arrogantly and selfishly consumed.
The duty of the latter being the yielding and submitting of the believer to picking up the painful cross of Jesus Christ, resulting in the mortification of the deeds of the vile body by the all-powerful, artistic moving of the Creator and Savior God of the universe.
So do we then, the second, condemn the first? No, not at all. But rather we share the Good News of God’s great grace, that they too may believe not in themselves, but laying down their lives they take up the real and genuine power of the One who makes all things possible, even the salvation of filthy sinners by a holy and just God.
13For if you live according to the flesh you will die; but if by the Spirit you put to death the deeds of the body, you will live. 14For as many as are led by the Spirit of God, these are sons of God. Romans 8:13-14
Thoughts written while reading “The Mortification of Sin” by John Owen (Chapter 1).