Thomas Boston: How And Why To Distinguish Between Law And Gospel

THERE is little more in all this, (viz. “The Marrow,”) to be attributed to me than the very gathering and composing of it. That which I aim at, and intend therein, is to show unto myself, and others that shall read it, the difference betwixt the Law and the Gospel,—a point, as I conceive, very needful for us to be well instructed in, and that for these reasons:—First, Because, if we be ignorant thereof, we shall be very apt to mix and mingle them together, and so to confound the one with the other; which, as Luther on the Galatians, p. 31, truly says, “doth more mischief than man’s reason can conceive;” and therefore he doth advise all Christians, in the case of justification, to separate the Law and the Gospel as far asunder as heaven and earth are separated.

Secondly, Because if we know right how to distinguish betwixt them, the knowledge thereof will afford ns no small light towards the true understanding of the Scripture, and will help us to reconcile all such places, both in the Old and New Testament, as seem to be repugnant; yea, and it will help us to judge aright of cases of conscience, and quiet our own conscience in time of trouble and distress; yea, and we shall thereby be enabled to try the truth and falsehood of all doctrines: wherefore, for our better instruction in this point, we are first of all to consider and take notice what the law is, and what the gospel is.

Now, the law is a doctrine partly known by nature, teaching us that there is a God, and what God is, and what he requires us to do, binding all reasonable creatures to perfect obedience, both internal and external, promising the favour of God, and everlasting life to all those who yield perfect obedience thereunto, and denouncing the curse of God and everlasting damnation to all those who are not perfectly correspondent thereunto.

But the gospel is a doctrine revealed from heaven by the Son of God, presently after the fall of mankind into sin and death, and afterwards manifested more clearly and fully to the patriarchs and prophets, to the evangelists and apostles, and by them spread abroad to others; wherein freedom from sin, the curse of the law, the wrath of God, death, and hell, is freely promised for Christ’s sake unto all who truly believe on his name.

2dly, We are to consider what the nature and office of the law is, and what the nature and office of the gospel is.

Now, the nature and office of the law is to show unto us our sin, (Rom. 3:20,) our condemnation, our death, Rom. 2:1; 7:10. But the nature and office of the gospel is to show unto us, that Christ has taken away our sin, (John 1:29,) and that he also is our redemption and life, Col. 1:14; 3:4. So that the LAW is a word of wrath, Rom. 4:14; but the GOSPEL is a word of peace, Eph. 2:17.

3dly, We are to consider where we may find the law written, and where we may find the gospel written.

Now, we shall find this law and this gospel written and recorded in the writings of the prophets, evangelists, and apostles, namely, in the books called the Old and New Testament, or the Scriptures. For, indeed, the law and the gospel are the chief general heads which comprehend all the doctrine of the Scriptures; yet we are not to think that these two doctrines are to be distinguished by the books and leaves of the Scriptures, but by the diversity of God’s Spirit speaking in them: we are not to take and understand whatsoever is contained in the compass of the Old Testament to be only and merely the word and voice of the law; neither are we to think that whatsoever is contained within the compass of the bookscalled the New Testament is only and merely the voice of the gospel; for sometimes in the Old Testament God does speak comfort, as he comforted Adam, with the voice of the gospel; sometimes also in the New Testament he does threaten and terrify, as when Christ terrified the Pharisees. In some places, again, Moses and the prophets do play the evangelists; inasmuch that Hierom doubts whether he should call Isaiah a prophet or an evangelist. In some places, likewise, Christ and the apostles supply the part of Moses: Christ himself, until his death, was under the law, which law he came not to break, but to fulfil; so his sermons made to the Jews, for the most part, run all upon the perfect doctrine and works of the law, showing and teaching what we ought to do by the right law of justice, and what danger ensues in the non-performance of the same. All which places, though they be contained in the book of the New Testament, yet are they to be referred to the doctrine of the law, ever having included in them a privy exception of repentance and faith in Jesus Christ. As for example, where Christ thus preaches, “Blessed are the pure in heart, for they shall see God,” Matt. 5:8. Again, “Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven,” Matt. 18:3. And again, “He that doth the will of my Father which is in heaven, shall enter into the kingdom of heaven,” Matt. 7:22. And again, the parable of the wicked servant cast into prison, for not forgiving his fellow, Matth. 18:30; the casting of the rich glutton into hell, Luke 16:23. And again, “He that denieth me before men, I will deny him before my Father which is in heaven,” Luke 12:9; with divers such other places, all which, I say, do appertain to the doctrine of the law.

Wherefore, in the fourth place, we are to take heed, when we read the Scriptures, we do not take the gospel for the law, nor the law for the gospel, but labour to discern and distinguish the voice of the one from the voice of the other: and if we would know when the law speaks, and when the gospel speaks, let us consider and take this for a note, That when in Scripture there is any moral work commanded to be done, either for eschewing of punishment, or upon promise of any reward, temporal or eternal; or else when any promise is made, with the condition of any work to be done, which is commanded in the law, there is to be understood the voice of the law.

Contrariwise, where the promise of life and salvation is offered unto us freely, without any condition of any law, either natural, ceremonial, or moral, or any work done by us, all those places, whether we read them in the Old Testament, or in the New, are to be referred to the voice and doctrine of the gospel; yea, and all those promises of Christ coming in the flesh, which we read in the Old Testament, yea, and all those promises in the New Testament, which offer Christ upon condition of our believing on his name, are properly called the voice of the gospel, because they have no condition of our mortifying annexed unto them, but only faith to apprehend and receive Jesus Christ; as it is written, (Rom. 3:22,) “For the righteousness of God, which is by faith of Jesus Christ unto all, and upon all that believe,” &c.

Briefly, then, if we would know when the law speaks, and when the gospel speaks, either in reading the word, or in hearing it preached; and if we would skilfully distinguish the voice of the one from the voice of the other, we must consider,

Law. The law says, “Thou art a sinner, and therefore thou shalt be damned;” Rom. 7:2; 2 Thess. 2:12.

Gos. But the gospel says, No; “Christ Jesus came into the world to save sinners;” and therefore “believe on the Lord Jesus Christ, and thou shalt be saved,” 1 Tim. 1:15; Acts 16:31.

Law. Again the law says, “Knowest thou not that the unrighteous shall not inherit the kingdom of God; be not deceived,” &c. 1 Cor. 6:9. And therefore thou being a sinner, and not righteous, shall not inherit the kingdom of God.

Gos. But the gospel says, “God has made Christ to be sin for thee, who knew no sin; that thou mightest be made the righteousness of God in him, who is the Lord thy righteousness,” Jer. 23:6.

Law. Again the law says, “Pay me that thou owest me, or else I will cast thee into prison,” Matt. 18:28, 30.

Gos. But the gospel says, “Christ gave himself a ransom for thee,” 1 Tim. 2:6; “and so is made redemption unto thee,” 1 Cor. 1:30.

Law. Again the law says, “Thou hast not continued in all that I require of thee, and therefore thou art accursed,” Deut. 27:6.

Gos. But the gospel says, “Christ hath redeemed thee from the curse of the law, being made a curse for thee,” Gal. 3:13.
Law. Again the law says, “Thou art become guilty before God, and therefore shalt not escape the judgment of God,” Rom. 3:29; 2:3.

Gos. But the gospel says, “The Father judgeth no man, but hath committed all judgment to the Son,” John 5:12.

And now, knowing rightly how to distinguish between the law and the gospel, we must, in the fifth place, take heed that we break not the orders between these two in applying the law where the gospel is to be applied, either to ourselves or to others; for albeit the law and gospel, in order of doctrine, are many times to be joined together, yet, in the case of justification, the law must be utterly separated from the gospel.

—Thomas Boston, The Whole Works of Thomas Boston: An Explication of the Assembly’s Shorter Catechism, ed. Samuel M‘Millan (Aberdeen: George and Robert King, 1850), 7.459–62.

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  • R. Scott Clark
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    R.Scott Clark is the President of the Heidelberg Reformation Association, the author and editor of, and contributor to several books and the author of many articles. He has taught church history and historical theology since 1997 at Westminster Seminary California. He has also taught at Wheaton College, Reformed Theological Seminary, and Concordia University. He has hosted the Heidelblog since 2007.

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  1. A helpful reading – it seems that Boston’s willingness to say that the law and gospel are joined on points *other* than justification stands in contrast to the radical lutherans like Elert and Forde (and their students).

  2. Dr. Clark – I don’t think they do, either, yet it seems like their teaching has gained a hearing in recent years. On the bright side, some orthodox Lutherans have risen up to counter the teaching with a more robust defense of orthodoxy. Very helpful.

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