The Knowledge of Sin by the Law - Romans 3:20

by Archibald Alexander

For by to law is the knowledge of sin.— Rom. iii. 20.

The Jews, and particularly the Pharisees, prided themselves on the high privileges they enjoyed, as being the chosen people of God, sealed with his seal, the objects of a special providence, and the descendants of Abraham, the friend of God. They seem, therefore, to have entertained the flattering opinion, that they were in a safe state, and that the threatenings contained in the Scriptures did not relate to them, but to the heathen, and apostates. The apostle in this epistle, takes great pains to convince them of their error; and after having proved, by a reference to known facts, the desperate wickedness of the heathen, proceeds to show, by irrefragable arguments, that the Jew was really in no safer condition than the Gentile; that both were naturally under condemnation; that all had sinned, and come short of the glory of God. He insists upon it, that the curses denounced against sinners, in the written law, related rather to the Jews, than to the Gentiles;, "for," says he, "what the law saith, it saith to them that are under the law; that every mouth may he stopped, and all the world may become guilty before God." The necessary inference from this universality of sin and guilt is, that by the deeds of the law no flesh can be justified in the sight of God : for the evident reason, that "by the law is the knowledge of sin." That law which convinces of sin, must of necessity condemn, but cannot justify. A sentence of justification is grounded on the fact, that the law has been perfectly obeyed, or has been fully satisfied. But if every man may be convicted of sin by the law, then, evidently, the impossibility of being justified by the deeds of the law, that is, by our own obedience to the law, is manifest.

Our object, in the following discourse, is to make some observations on the nature of the law—and to consider the import of the declaration, that " by the law is the knowledge of sin."

Another apostle gives us a comprehensive definition of sin, which coincides exactly with the import of our text. " Sin" says he, " is the transgression of the law" By transgression here, we should understand every want of conformity to the law, for this is the true meaning of the original term here used.

The definition, therefore, includes sins of omission, as well as of commission. Sin has no existence but in relation to the law; for, as the apostle reasons, " where there is no law, there is no transgression." The law maybe compared to a straight rule. Sin is the deviation from this rule, and the enormity of the sin may be measured by the degree of obliquity in any act. Laws are of different kinds, according to the nature of the subject regulated. The universe is under law, for the Creator is a God of order; and acts uniformly in the government of his creatures, when they are placed in the same circumstances. But our inquiry, at present, relates to the law given to man, as an accountable moral agent. This law was originally written on the human heart, where vestiges of it are still discernible. It has, therefore, been called, the law of nature. But as through the prevalence of ignorance and error, this law has been greatly defaced in all men, and in the minds of some, almost obliterated ; it pleased God to make a full revelation of it, comprehending all moral duty, under two great commandments, enjoining love to God and our neighbour; and to show how these general precepts were to be carried out in their application to practice, ten commandments were engraven by the finger of God, on two tables of stone. These summarily comprehend the whole duty of man.

But as the spiritual and perfect nature of the law was misapprehended by the Jews, and many of the precepts set aside by the false glosses of the Scribes and Pharisees, our blessed Lord, in his public discourses, gave the true interpretation of the law, and repudiated the erroneous opinions of moral duty, which had been long inculcated on the people, by their teachers. Many, in our day, also, entertain very inadequate ideas of the nature and obligations of the law. By some it is believed and taught, that the strictness of the moral law is now relaxed, and that a milder and more indulgent rule of life, has succeeded to the law given to our first parents, while in a state of innocence. But no conclusion is more certain from both reason and Scripture, than the indispensable, immutable nature of the law. As it arises from the nature of God, and the relation of man to him ; and is really, a transcript, as far as it goes, of the moral attributes of God, it never can be relaxed, nor undergo any change in its principles. As God is infinitely holy, he never can require less holiness in his creatures, than they are capable of. The idea of bringing down the law to adapt it to the ability of fallen man is absurd; for on that principle, the more any man was under the dominion of sin, the less would the law require of him. This principle would go far to nullify the law altogether, and render it utterly impossible to ascertain precisely what it requires. It is a sound principle, that any inability arising from a depraved nature, has no tendency to alter the demands of the law. The law, therefore, ever remains the same, to the man in innocence—to the man under sin—to the man partially sanctified, and to the saint in heaven. It is the standard of human perfection, and its moral obligation can never cease.

Antinomians hold, that in consequence of Christ's perfect obedience, the law has no demands on those in whose place he obeyed. They pretend, therefore, that the moral law is not obligatory on Christians, to whom the righteousness of Christ is imputed. This is a gross abuse of a cardinal doctrine. And if the thing were true, it would be no privilege, but a real detriment to the believer; for he finds that the keeping of the commandments of God, even in this world, is attended with a great reward.

Others, again, entertain the opinion that the law was altered and improved by our Lord; and they refer to the sermon on the mount. But the alteration is not in the law itself, but in the interpretation of the law; the erroneous opinions respecting some things were set aside, in that discourse. But our Lord, when he lays down the precepts of the law, gives us precisely the great principles of duty which are found in the law of Moses. God is the same from everlasting to everlasting, and his law must be the same.

The law of God is not an arbitrary rule, but, as was said, is founded on the nature of man, and the relation in which he stands to God, and his fellow creatures. Reason dictates, that a rational, choosing agent, should employ all his faculties, and direct all his actions, to the glory of his Creator; and as this end can in no other way be attained, than by obeying the will of God, therefore, the manifestation of the divine will must be the law of all rational creatures. And as to the measure of obedience required, it is evident, that there can be no limit to its perfection, except that which necessarily arises from the limited nature of the faculties of creatures. The idea intended to be communicated is, that all the faculties and affections of every rational creature, are reasonably put into requisition, to glorify the Creator. It cannot be supposed, that any thing less than entire devotedness to the will of God should be required; or when required, that there should not be a moral obligation on the creature to obey.

That the law of God requires perfect obedience is self-evident; for what is perfect obedience but that which the law demands? To suppose that any law could be satisfied by an imperfect obedience, involves the absurdity, that the law requires something which it does not require. It may, perhaps, appear to a mind alienated from God, to be a hardship, to be under obligation to love and serve God continually, to the full extent of its powers. But if the mind were renewed, and the law and service of God were found to be the happiness and delight of the soul, then it would no longer appear to be a hardship to be required to love God with all the heart. No man will complain of that which is necessary to his highest felicity. But if something less than the entire heart were required, we might ask, how much less ? And if not required to serve God, all our time, what proportion should be devoted to his service ? But, if it should be alleged, that uniform perfection of obedience ought not to be insisted on, since man is a fallible, erring creature ; but that there ought to be some indulgence granted to the frailties of human nature, I would reply, that if any indulgence to sin be allowed, there can be no limit fixed to which it should be extended. Such a principle would destroy the obligation of the moral law. There ought to be no indulgence allowed to that which deforms the image of God in man, and which tends to destroy or lessen his own happiness. Again, these frailties belong not to our nature, as it came perfect from the hand of the Creator, but belong to our sinful nature, to which a holy law can show no indulgence. And, as before intimated, our happiness is intimately connected with universal obedience. No creature can render to God as much love and reverence as he deserves. If the capacity of any such being were enlarged a hundred, or a thousand fold, the obligation to exercise all his powers in loving and serving God, would be as complete as to serve him with the ability which he now possesses.

Since then we are capable of paying so small a part of what we owe to our Creator, is it not most ungrateful, as well as unreasonable, to wish to detract from his service any part of what we are capable of rendering ? Would not this be the worst kind of robbery, even the robbery of God ? Such murmurings against the demands of the law, are after all, founded on some undefined notion, that there is some injustice in the case; as if it would be a privilege and an increase of desirable liberty, if we were not under this obligation, to render perfect obedience, at all times. Now, although this is the language of a depraved heart, yet it can easily be demonstrated, that the idea is not consonant to the truth; and that the law of God is not only holy and just, but wise and good, and the very best and happiest rule under which the creature could be placed.

The ground of difficulty is in our depraved nature, which has lost all relish for the service of God. The mind of man must be active, and no species of action is in itself so morally excellent, and accompanied with so much pleasure, as the love and service of God. And to a soul rightly constituted, the most intense exercise of holy affection is so far from being felt as a burden or task, that it affords the sweetest pleasure of which we ever partake. If the heart were right, even as God made it, there would be no difficulty experienced in complying with the command to love the Lord our God, with all our heart, mind and strength. And the same may be said respecting the love of our neighbour. It is our sinful selfishness which renders this duty difficult, and causes some to think that the command to love our neighbour as ourselves is not only unreasonable, but impossible.

To be perfectly obedient to the commandments of God is to be completely happy. Surely, no one ought to complain of being required to pursue his own greatest happiness. The angels in heaven are happy, because they are holy, and always employed in holy exercises and duties. From what has been said, the truth of the apostle's declaration is evident, that " the law of God is holy, and the commandment holy, just and good."

The proposition contained in our text, that " by the law is the knowledge of sin," is so evident from the definition of sin, given by the apostle John, that there does not appear to be any necessity for further demonstration of its truth. All that will be requisite, in regard to this point, will be to make a practical use and application of the evident truth.

If our actions had always been conformable to the precepts of God, the closest application of the law would produce no conviction of sin. And that such perfection of obedience is possible to human nature is manifest, by the example of Christ, who possessed all the faculties and appetites which are the constituents of human nature; and was in all points tempted as we are; and yet "he knew no sin," though he knew the law perfectly. He could appeal to his bitterest enemies and say, "which of you convicts me of sin ?" He continued from the beginning to the end of his life, " holy, harmless, undefiled and separate from sinners, and no guile was found in his mouth." From this perfect example it is manifest, that the law of God is perfectly adapted to human nature, and that it may be constantly obeyed by the faculties which we possess, were it not for sin which dwelleth in us.

If the moral law is the measure of our duty, then just so far as man has deviated from this perfect rule, just so far the law shows that he is a sinner. And, whereas the law demands a positive compliance with its requisitions, as well as prohibits the doing of certain acts, it follows, that there are sins of omission as well as sins of commission. And, indeed, as love is the main thing which the law requires, the defect of this holy affection is the evil fountain from which all other sins take their rise. Sins of commission could never be committed until there is some defect in the strength and constancy of this holy principle. Human nature may be compared to a complicated machine, which has within it, powerful springs which keep it in operation. But such a machine requires a balance or regulator, which may preserve all the parts in their proper places, and give due energy and direction to every part. If the balance wheel, be taken away, the machine loses none of its power, but its action becomes irregular, and no longer subserves the purpose for which it was put in motion. It moves, it may be, more rapidly than before, but to its own ruin. So it is with man. He is an agent, possessing active powers, and a variety of appetites, affections, and passions, which require to be regulated, and properly directed; otherwise, their most powerful action will be of a ruinous character. Now if it be asked, what was made the regulating principle in man, to which all his powers should be subservient? Two things are necessary to give harmony and a right direction to the complex faculties and affections of man. The first is, light; the second, love. Or, to speak more correctly, an enlightened conscience, and uniform and constant love to God. But when sin was introduced, the mind was blinded, conscience misdirected, and the love of God in the soul was extinct. The man however, still remains a moral agent, and an accountable creature; otherwise, he would be incapable of sinning.

Although the mind of man has fallen into an awful state of blindness, and disorder, yet conscience is not obliterated : as far as it has light, it still remonstrates against the commission of sin, and utters its voice of condemnation, when sin has been committed Happily, some actions are intuitively seen to be morally wrong, and by no sophistry can the soul be persuaded to approve them. But in regard to a large part of sinful acts, or omissions, most men remain ignorant of them, because they know not the extent and spirituality of the law. This is remarkably the case m regard to the affections and purposes of the heart, in which sin has its origin, and its essence. And mere theoretical knowledge of the law is not sufficient: many by means of a good religious education, possess this; and yet feel no deep conviction of the depth and turpitude of the sin of their hearts. It requires the convincing light of the Holy Spirit to shine in upon the conscience, and to cause the mind to view itself, as it were in the mirror of God's holy law. This conviction by the law, is the common preparatory work, before mercy is bestowed. " The whole need not a physician, but they who are sick." It is unnecessary to perplex ourselves with doubts about our spiritual condition, because we may not have had, in our experience, as distinct a work of the law, as some others. If we are true Christians, we do now possess such a spiritual knowledge of the law, that we are daily convinced of our want of conformity to it, and do see and feel something of the odious nature of the sin which dwells within us. Now, this is the only kind of conviction, which is essential to true religion. The greatest degree of mere legal conviction is no evidence of a renewed mind. The devils and impenitent sinners will all have this kind of conviction, at the day of judgment, and to all eternity. If, therefore, we have been led to see and feel the intrinsic evil of sin, we need not be troubled because we cannot distinctly trace, in our experience, what is commonly called a law work; for, though conviction of sin by the Holy Spirit, is essential to a true Christian, yet this is always included in true repentance; repentance, indeed, founded on just views of the turpitude of sin, as seen by the light of the Spirit, in the mirror of God's holy law. This conviction of sin increases in the mind of the true believer, in proportion to his growth in grace. The more eminent any man is in piety, the deeper will be his sense of the inward defilement of sin, and the greater his self-abhorrence on account of it, according to that of Job " I have heard of thee by the hearing of the ear, but now mine eye seeth thee, wherefore I abhor myself, and repent in dust and ashes."

They who dream of a perfection in this life, which leads them to think, that they are free from all sin, evidently have not the same kind of religion as the patriarch Job, who is declared to have been " a perfect and upright man." Such are evidently ignorant of the purity and spirituality of the law of God; or ignorant of the true state of their own hearts. "Whoever obtains a spiritual view of the law, will possess by the law, a right knowledge of sin. There is no better evidence of an enlightened mind, and renewed heart, than just views and feelings in regard to our own sins; and especially, the sins of the heart. It seems, at first view, wonderful, that any person should be so blinded as to think and say, in the face of express declarations of Scripture to the contrary, that he has no sin. But there are many blinding influences which operate on the human heart, which itself is declared to be " deceitful above all things." And among these none is more efficient than spiritual pride. The selfish heart rejoices and glories in the idea of its own superiority to others; and under this illusion, with avidity admits the persuasion, that all its iniquities are purged, and that it needs no further purification; and is henceforth free from the necessity of mortifying the deeds of the body, and crucifying the flesh with its affections and lusts; and from the necessity of asking for the pardon of daily sins.

That the majority of men possess very inadequate ideas of the evil of sin, is evident from their contentment under its defilement. Many are not only contented to remain under the power of sin, but they embrace the odious monster with a wonderful avidity, and repel every attempt to deliver them from this mortal and evil disease. Even those who, for the sake of reputation, maintain an exterior free from gross transgressions, do often, cherish in their hearts ideas, desires, and purposes, which contain the very essence of iniquity; and yet they seem to have no discernment of the hateful nature of the lusts of the flesh and of the spirit, which they cherish in their hearts. They appear to be satisfied, like the Pharisee of old, if they can keep the outside of the cup and platter clean. How little the real evil of sin is perceived, even by professors of Christianity is manifest, from the little concern which they feel to be cleansed from all filthiness of the flesh and spirit. They do not groan as did the apostle Paul, under a painful sense of indwelling sin, but are very much at ease in Zion. If, indeed, under the power of temptation, they are guilty of some overt act of transgression, they are often deeply wounded, and discover much concern and sorrow for what they have done. But it is an evidence, that this concern, for the most part, springs from a selfish principle, that sins of greater turpitude are committed in the spirit, in the imaginations and desires of the heart, for which they feel little or no regret. But souls under the sanctifying influence of the Holy Spirit, are led to see that their chief disease is one of the heart; and before God, they mourn daily over their want of holy feelings and emotions, and on account of the many evils which they, by the application of the law, detect in themselves. And from the evil thoughts and desires which often spring up in them, they are convinced that the heart itself, which generates such sinful thoughts, must be desperately wicked. So far indeed, as it has been renewed, there is another principle implanted; but the old man has great strength, and even when it was hoped that particular sins were completely mortified, yet afterwards, under circumstances favourable to their exercise, they sprout anew, and with vigour strive for the mastery. The great business of the Christian is to oppose and mortify these corruptions, which remain after conversion, in the regenerate. Hence there must be a perpetual conflict between the flesh and the Spirit—between the old man and the new. And although the real Christian is often discouraged with his want of success, in this warfare, yet the Captain of salvation has assured him of ultimate victory. None do truly engage in this warfare but such as have been enlightened to see the evil, of sin as reflected from the mirror of the holy law. And the more they are convinced of sin, the more do they have recourse to the fountain opened for sin and uncleanness.

The use which we should make of this subject is

1. To endeavour to get clear views of the extent, spirituality, and purity of the moral law, in order that we may know something of the multitude and malignity of our sins. We should, therefore, not only learn the nature of the law as exhibited in the Holy Scriptures, but should with conscientious fidelity and diligence apply the rule to our own hearts and lives, by a frequent and impartial examination of ourselves. Every hour spent in such self-scrutiny will reveal to us evils which before we had not noticed. And no sin can be mortified and subdued, until it is detected, and its evil nature discerned. And, as all true spiritual knowledge is from the Holy Ghost, we should incessantly pray for this inestimable blessing, which Christ has so emphatically taught, will be freely given to every one who asks—that is, who asks with faith and importunity.

2. As the law convicts every man of sin, justification by it is impossible; for even one sin would render it impossible for the transgressor to receive a sentence of acquittal; how much more impossible is it, when our sins are literally innumerable!

The only condition of justification by the law, is perfect obedience, and no such obedience can be rendered by any mere man; but it has been rendered by Christ, in our nature, for he was made under the law, and fulfilled all righteousness. And of this ground of acceptance the sinner is warranted, by the free call of the gospel, to avail himself, by believing with all his heart in the Lord Jesus Christ.

3. If the law discovers sin of every kind to be a base and odious thing, we should be solicitous to be cleansed from its defilement; and, in order"to this, should come often to the fountain for sin and uncleanness, opened by the death of Christ; that is, we should by faith apply to the blood of sprinkling, and should seek daily to purify ourselves from all filthiness of the flesh and spirit. We should earnestly and importunately offer up the petition, which Christ offered in his intercessory prayer, 14 Sanctify us through thy truth, thy word is truth." The word rendered effectual by the Holy Spirit, is the efficient means of cleansing to the souls of believers. We should ply this work every day; for it is carried on by the use of means, and our success in it depends very much on the diligence and fidelity with which we use the means of God's appointment. " Blessed," says Christ" are they that hunger and thirst after righteousness, for they shall be filled. Blessed are the pure in heart, for they shall see God. Be ye holy, for I am holy."

4. A spiritual knowledge of the law is the true source of evangelical repentance. As sin is a dis-conformity to the law, and its turpitude is seen in this glass, the sight of it will fill the soul with sorrow and compunction, and work such a hatred of sin as will effectually turn away the soul from the abominable thing which God hates. This view of sin, in its deformity and vileness, will also* cause the soul not only to mourn, but to be ashamed and confounded in the presence of God. And as this quality of baseness and defilement belongs to all sin, true repentance will consist in a hearty aversion to all sin, and a fixed purpose to forsake it, which will show itself by reformation of life.

5. The knowledge of sin, produced by the law, will have a tendency to make the true penitent willing to leave the present state, and forsake the clay tabernacle, as sin cleaves to the soul as long as it remains here, and these vile bodies must be laid in the dust, before they will be purified from the disorder which sin has introduced. As perfection in holiness is the blessedness reserved for the future state of the believer, he will often direct a longing look to those regions of purity, into which neither sin nor sorrow can ever enter. This delightful hope he cherishes, and it leads him, while detained below, to seek for purity. " He," says the apostle John, " that hath this hope in him, purifieth himself, even as He is pure." How sweet the rest, when all contest with sin and temptation shall cease! How glorious the state in which we shall see no longer darkly through a glass, but face to face, and where we shall know even as we are known!

6. The most important benefit of the knowledge of sin, by the law, is, that it shows us our absolute need of a better righteousness than our own, and impels us to look for salvation, to the cross of Christ. The law is a schoolmaster to bring us unto Christ; and, although this had primary reference to the ceremonial law, the moral law is not excluded; but is now made use of to drive sinners to that refuge, which God, in mercy, has prepared for them. Commonly the first concern of the awakened soul has relation to the law, which he now begins to see to possess a binding obligation, and that he has broken it in innumerable instances, in thought, word and deed. The application of the law to the conscience of an awakened sinner, puts him, at first, on earnest efforts to repair the breach which he has made. He now strives by prayers and tears, and various human devices, to make satisfaction for his sins; but the more he strives to raise himself out of the horrible pit and miry clay, the deeper he sinks, and like a prisoner in a dark deep pit, no effort that he can make, has any tendency to extricate him from his helpless condition. But when having exhausted all his efforts, without success, he is ready to despair of salvation, he hears the voice of a kind Deliverer, inviting him to look unto him and be saved. It is as though one let down a rope to the helpless prisoner. All he has to do is to take fast hold, and he is drawn up and finds himself in safety, and at liberty. So the convinced sinner seizes the invitations of the gospel, with the strong grasp of faith, and behold! he is brought out of darkness into the marvellous light of the gospel, and from a state of condemnation to complete justification. If I now speak to any convinced, discouraged soul, who finds that he can do nothing to remove either the guilt or defilement of sin, I would earnestly and affectionately exhort such to take immediate refuge under the cross. The crucified Redeemer sends forth an influence from this point, which effectually draws the hearts of sinners to himself. " Look unto me and be ye saved, all the ends of the earth, for I am God, and there is none beside me." As Moses lifted up the brazen serpent in the wilderness for the healing of those who were dying by the venomous bite or sting of the fiery serpents; so the Son of Man has been lifted up, that whosoever believeth on him might have everlasting life. All that was required in the former case was to look, and all that is necessary to salvation now is faith, which is nothing else but looking unto Jesus for his help and deliverance.


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