John Calvin's Harmony of the Ten Commandments or Moral Law is his commentary on the books Exodus,
Leviticus, Numbers, and Deuteronomy. Whereas the majority of Calvin's commentaries are chronologically arranged--beginning with the first verse in a book, and ending with the last--Harmony of the Law is arranged topically, for Calvin believed that his topical arrangement would better present the various doctrines of "true piety." A remarkable commentary, Harmony of the Law contains Calvin's discussion of the Ten Commandments, the usefulness of the law, and the harmony of the law. Harmony of the Law instructs readers in both the narrative history of the Old Testament and the practical importance and use of the Old Testament teachings. Harmony of the Law is highly recommended, and will demonstrate to a reader why Calvin is regarded as one of the
best commentators of the Reformation.
John Calvin Ten Commandments
John Calvin writes extensively about the Ten CommandmentsThe preface to the Ten Commandments is, 'I am the Lord thy God.'
The preface to the preface is, 'God spake all these words, saying,' &c. This is like the sounding of a trumpet before a solemn proclamation. Other parts of the Bible are said to be uttered by the mouth of the holy prophets (Luke 1: 70), but here God spake in his own person.
How are we to understand that, God spake, since he has no bodily parts or orgasms of speech?
God made some intelligible sound, or fanned a voice in the air, which, to the Jews was as though God himself was speaking to them. Observe:
(1) The lawgiver. 'God spake.' There are two things requisite in a lawgiver.
 Wisdom. Laws are founded upon reason; and he must be wise that makes laws. God, in this respect, is most fit to be a lawgiver: 'he is wise in heart.' Job 9: 4. He has a monopoly of wisdom. 'The only wise God.' 1 Tim 1: 17. Therefore he is the fittest to enact and constitute laws.
 Authority. If a subject makes laws, however wise they may be, they want the stamp of authority. God has the supreme power in his hand: he gives being to all; and he who gives men their lives, has most right to give them their laws.
(2) The law itself. 'All these words.' That is, all the words of the moral law, which is usually styled the decalogue, or ten commandments. It is called the moral law because it is the rule of life and manners. The Scripture, as Chrysostom says, is a garden, and the moral law is the chief flower in it: it is a banquet, and the moral law is the chief dish in it.
The moral law is perfect. 'The law of the Lord is perfect.' Psa 19: 7. It is an exact model and platform of religion; it is the standard of truth, the judge of controversies, the pole-star to direct us to heaven. 'The commandment is a lamp.' Prov 6: 23. Though the moral law be not a Christ to justify us, it is a rule to instruct us.
The moral law is unalterable; it remains still in force. Though the ceremonial and judicial laws are abrogated, the moral law delivered by God's own mouth is of perpetual use in the church. It was written in tables of stone, to show its perpetuity.
The moral law is very illustrious and full of glory. God put glory upon it in the manner of its promulgation.
 The people, before the moral law was delivered, were to wash their clothes, whereby, as by a type, God required the sanctifying of their ears and hearts to receive the law. Exod 19: 10.
 There were bounds set that none might touch the mount, which was to produce in the people reverence to the law. Exod 19: 12.
 God wrote the law with his own finger, which was such an honour put upon the moral law, as we read of no other such writing. Exod 31: 18. God by some mighty operation, made the law legible in letters, as if it had been written with his own finger.
 God's putting the law in the ark to be kept was another signal mark of honour put upon it. The ark was the cabinet in which He put the ten commandments, as ten jewels.
 At the delivery of the moral law, many angels were in attendance. Deut 33: 2. A parliament of angels was called, and God himself was the speaker.
Use one. Here we may notice God's goodness, who has not left us without a law. He often sets down the giving his commandments as a demonstration of his love. 'He has not dealt so with any nation: and as for his judgments they have not known them.' Psa 147: 20. 'Thou gavest them true laws, good statutes and commandments.' Neh 9: 13. What a strange creature would man be if he had no law to direct him! There would be no living in the world; we should have none born but Ishmaels - every man's hand would be against his neighbour. Man would grow wild if he had not affliction to tame him, and the moral law to guide him. The law of God is a hedge to keep us within the bounds of sobriety and piety.
Use two. If God spake all these words of the moral law, then it condemns:
(1) The Marcionites and Manichees, who speak lightly, yea, blasphemously, of the moral law; who say it is below a Christian, it is carnal; which the apostle confutes, when he says, 'The law is spiritual, but I am carnal.' Rom 7: 14.
(2) The Antinomians, who will not admit the moral law to be a rule to a believer. We say not that he is under the curse of the law, but the commands. We say not the moral law is a Christ, but it is a star to lead to Christ. We say not that it saves, but sanctifies. They who cast God's law behind their backs, God will cast their prayers behind his back. They who will not have the law to rule them, shall have the law to judge them.
(3) The Papists, who, as if God's law were imperfect, and when he spake all these words he did not speak enough, add to it their canons and traditions. This is to tax God's wisdom, as if he knew not how to make his own law. This surely is a high provocation. 'If any man shall add to these things, God shall add unto him the plagues that are written in this book.' -Rev 22:18. As it is a great evil to add anything to a man's sealed will, so much more to add anything to the law which God himself spake, and wrote with his own fingers.
Use three. If God spake all the words of the moral law, several duties are enjoined upon us:
(1) If God spake all these words, then we must hear all these words. The words which God speaks are too precious to be lost. As we would have God hear all our words when we pray, so we must hear all his words when he speaks. We must not be as the deaf adder, which stoppeth her ears: he that stops his ears when God cries, shall cry himself, and not be heard.
(2) If God spake all these words, then we must attend to them with reverence. Every word of the moral law is an oracle from heaven. God himself is the preacher, which calls for reverence. If a judge gives a charge upon the bench, all attend with reverence. In the moral law God himself gives a charge, 'God spake all these words;' with what veneration, therefore, should we attend! Moses put off his shoes from his feet, in token of reverence, when God was about to speak to him. Exod 3: S, 6.
(3) If God spake all these words of the moral law, then we must remember them. Surely all God speaks is worth remembering; those words are weighty which concern salvation. 'It is not a vain thing for you, because it is your life.' Deut 32: 47. Our memory should be like the chest in the ark where the law was kept. God's oracles are ornaments, and shall we forget them? 'Can a maid forget her ornaments?' Jer 2: 32.
(4) If God spake all these words, then believe them. See the name of God written upon every commandment. The heathens, in order to gain credit to their laws, reported that they were inspired by the gods at Rome. The moral law fetches its pedigree from heaven. Ipse dixit. God spake all these words. Shall we not give credit to the God of heaven? How would the angel confirm the women in the resurrection of Christ? 'Lo (said he), I have told you.' Matt 28: 7. I speak in the word of an angel. Much more should the moral law be believed, when it comes to us in the word of God. 'God spake all these words.' Unbelief enervates the virtue of God's word, and makes it prove abortive. 'The word did not profit, not being mixed with faith.' Heb 4: 2. Eve gave more credit to the devil when he spake than she did to God.
(5) If God spake all these words, then love the commandments. 'Oh, how love I thy law! it is my meditation all the day.' Psa 119: 97. 'Consider how I love thy precepts.' Psa 119: 159. The moral law is the copy of God's will, our spiritual directory; it shows us what sins to avoid, what duties to pursue. The ten commandments are a chain of pearls to adorn us, they are our treasury to enrich us; they are more precious than lands of spices, or rocks of diamonds. 'The law of thy mouth is better unto me than thousands of gold and silver.' Psa 119: 72. The law of God has truth and goodness in it. Neh 9: 13. Truth, for God spake it; and goodness, for there is nothing the commandment enjoins, but it is for our good. O then, let this command our love.
(6) If God spake all these words, then teach your children the law of God. 'These words, which I command thee this day, shall be in thy heart, and thou shalt teach them diligently unto thy children.' Deut 6: 6, 7. He who is godly, is both a diamond and a loadstone: a diamond for the sparkling of his grace, and a loadstone for his attractive virtue in drawing others to the love of God's precepts. Vir bonus magis aliis prodest quam sibi [A good man benefits others more than himself]. You that are parents, discharge your duty. Though you cannot impart grace to your children, yet you may impart knowledge. Let your children know the commandments of God. 'Ye shall teach them your children.' Deut 11: 19. You are careful to leave your children a portion: leave the oracles of heaven with them; instruct them in the law of God. If God spake all these words, you may well speak them over again to your children.
See examples of Christian billboards.
This condemns the church of Rome, which, instead of obeying the whole moral law, blots out one commandment, and dispenses with others. They leave the second commandment out of their catechism, because it makes against images; and to fill up the number of ten, they divide the tenth commandment into two. Thus, they incur that dreadful condemnation: 'If any man shall take away from the words of this book, God shall take away his part out of the book of life.' Rev 22: 19. As they blot out one commandment, and cut the knot which they cannot untie, so they dispense with other commandments. They dispense with the sixth commandment, making murder meritorious in case of propagating the Catholic cause. They dispense with the seventh commandment, wherein God forbids adultery; for the Pope dispenses with the sin of uncleanness, yea, incest, by paying fines and sums of money into his coffer. No wonder the Pope takes men off their loyalty to kings and princes, when he teaches them disloyalty to God. Some of the Papists say expressly in their writings, that the Pope has power to dispense with the laws of God, and can give men license to break the commandments of the Old and New Testament. That such a religion should ever again get foot in England, the Lord in mercy prevent! If God spake all the commandments, then we must obey all; he who breaks the hedge of the commandments, a serpent shall bite him.
Seven Deadly Sins An interesting historical perceptive from the middle ages, of the Seven Deadly Sins of the Bible.
Los Diez Mandamientos en Espanol Read the commandments in Spanish Los Diez Mandamientos en EspanolBut what man can obey all God's commandments?
To obey the law in a legal sense - to do all the law requires - no man can. Sin has cut the lock of original righteousness, where our strength lay; but, in a true gospel-sense, we may so obey the moral law as to find acceptance. This gospel obedience consists in a real endeavour to observe the whole moral law. 'I have done thy commandments' (Psa 119: 166); not, I have done all I should do, but I have done all I am able to do; and wherein my obedience comes short, I look up to the perfect righteousness and obedience of Christ, and hope for pardon through his blood. This is to obey the moral law evangelically; which, though it be not to satisfaction, yet it is to acceptation.
We come now to the preface itself, which consists of three parts:
I. I am the Lord thy God';
II. 'which have brought thee out of the land of Egypt';
III. 'out of the house of bondage'.