The spirit of sin, or inbred sin, technically called original sin, because it is inherited from Adam, is the state of heart out of which acts of sin either actually flow or tend to flow. Until this state is changed, the conquest of love over the soul is incomplete.
Regeneration introduces a power which checks the out breaking of original into actual sin, except occasional and almost involuntary sallies in moments of weakness or unwatchfulness. These are a source of grief and condemnation to the justified soul. They are a humiliating, yet only temporary defeat. For there is with all well instructed believers a resort to the blood of sprinkling, and a pleading of the promise, "If any man sin, we have an advocate with the Father, Jesus Christ the righteous."
We do not say that all justified persons experience these defeats. All may, and some doubtless do, live without condemnation from the glad moment of pardon; yet the testimony of the Church shows that these are rare exceptions. The majority, in the struggle with inbred sin, are not always victorious.
What is the difference then, between sin in a sinner, and sin in a believer? The same difference that there is between poison in a rattlesnake and the virus of that serpent injected into a healthy man. The venom is natural to the reptile. He delights in it, secretes and cherishes it with pleasure. But all the vital forces of the man resist the injected poison, and rally to thrust it out of the system.
We have shown elsewhere that the seventh chapter of the Epistle to the Romans was not designed by St. Paul as an ideal of the regenerate life, even in its lowest stages. But so true is the doctrine of sin in believers — inbred sin — sometimes breaking out against the enfeebled will, that a whole section of the Christian world have mistaken the struggles of an awakened legalist seeking Justification by good works, and failing through the ascendancy of depraved inclination, for the portrait of the Christian in his best estate in this life. This photograph of a Christless, convicted Jew, has, alas! been set before myriads of Christians as the masterpiece of that Jesus who came to save his people from their sins, the best specimen of his art as a Divine limner even when aided by the great transformer, the Holy Spirit.
This class of Christians do not need arguments to convince them of the possible existence of sin in believers. It is difficult for them to believe that they may live on the earth after sin is all destroyed.
Since nature abhors a vacuum in the spiritual as in the physical world, the complete and permanent annihilation of sin as a state of heart must be attended by the infusion of perfect love, by which we mean love in a degree commensurate with the utmost capacity of the soul. Hence the coup de grace, the deathblow which ends the war of love against sin, is a negative and limited work, to be followed by a work positive and unlimited. The first is the removal of all impurity, whether inherent or acquired; the second is being "filled with all the fullness of God." It is the adorning of the soul with all the fruit of the Spirit-love, joy, peace, long-suffering, gentleness, meekness, fidelity, patience, and temperance.
— Love Enthroned, Chapter 3.