Nature of Sin

Nor does he become the author of sin by his providence, because that lawlessness is nothing except a defect of operation, of which there cannot exist an author or efficient cause, but only a deficient cause, for which reason alone, the author of sin, insofar as it is such, is the creature, by its transgressing of the law.

Yet we are able to reconcile them easily enough, if we distinguish within sin its material element, namely, the habit or act that is the substrate of the wickedness, with which, inasmuch as it is physically good, God is not able not to concur as the efficient cause, without casting aside his own independence (Acts 17:28; Rom. 11:36), and its formal element, lawlessness (1 John 3:4), through which the act or habit is sin, whose author he cannot be, because the one set above all law cannot transgress the law.

There is a fallacy of the accident in the minor proportion; for the actions of the wicked are sins, not (per se) in themselves, in as far as they are actions; but by an accident on account of the want of righteousness, and of the perversity of the will of the ungodly, who do not observe this so as to follow in the action the will of God.

So far is it from being lawfully inferred from this that lust is not sin that by necessary consequence its sinfulness can thence be elicited. The effect ought to correspond with the cause; nor could lust bring forth actual sin unless it is itself sin.

Those who maintain that concupiscence is not sin, are wont to found on the passage of James, "Then, when lust has conceived, it bringeth forth sin," (James 1:15). But this is easily refuted: for unless we understand him as speaking only of wicked works or actual sins, even a wicked inclination will not be accounted sin. But from his calling crimes and wicked deeds the fruits of lust, and also giving them the name of sins, it does not follow that the lust itself is not an evil, and in the sight of God deserving of condemnation.

The Reformed on the contrary state that all concupiscence, which certainly inclines toward evil, is sin, insofar as (1) all such concupiscence is against the law (Rom. 7:7) and thus is lawlessness, in which sin fully consists (1 John 3:4).

This very thing cannot be conceived, how something by way of an internal habit could be the cause of sin and not be sin. An internal cause inclining to act well is good.

Nor does original sin cease to be sin because it was committed by us neither voluntarily nor knowingly; for it is enough that τὸ ἄνομον [to anomon, the lawless thing] is in our nature

Every spark of fire is fire, and will burn; so is every thing of the law of sin, the last, the least of it, -- it is enmity, it will poison, it will burn. … Mortification abates of its force, but doth not change its nature. Grace changeth the nature of man, but nothing can change the nature of sin. Whatever effect be wrought upon it, there is no effect wrought in it, but that it is enmity still, sin still.

Once more, it is named, "lust" or "concupiscence"; which is sin itself, and the mother of all sin

Accordingly, it is not valid to say: (1) it begets sin, therefore it is not sin. For a man, because he begets a man, does not cease to be a man; indeed, as we have said, it is sin by the very fact that it begets sin.

We must here observe, that not only are corrupt and disordered inclinations sins, but the thinking of evil, in as far as it is connected with an inclination and propensity to pursue it, or with a desire to practice it, is sin.