The Larger Catechism
98. Q. Where is the moral law summarily comprehended?
A. The moral law is summarily comprehended in the ten commandments, which were delivered by the voice of God upon Mount Sinai, and written by him in two tables of stone; and are recorded in the twentieth chapter of Exodus. The four first commandments containing our duty to God, and the other six our duty to man.
Scriptural Defense and Commentary
 Deuteronomy 10:4. And he wrote on the tables, according to the first writing, the ten commandments, which the LORD spake unto you in the mount out of the midst of the fire in the day of the assembly: and the LORD gave them unto me. Exodus 34:1-4. And the LORD said unto Moses, Hew thee two tables of stone like unto the first: and I will write upon these tables the words that were in the first tables, which thou brakest. And be ready in the morning, and come up in the morning unto mount Sinai, and present thyself there to me in the top of the mount. And no man shall come up with thee, neither let any man be seen throughout all the mount; neither let the flocks nor herds feed before that mount. And he hewed two tables of stone like unto the first; and Moses rose up early in the morning, and went up unto mount Sinai, as the LORD had commanded him, and took in his hand the two tables of stone.  Matthew 22:37-40. Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. This is the first and great commandment. And the second is like unto it, Thou shalt love thy neighbour as thyself. On these two commandments hang all the law and the prophets.
Most Christians believe that the Ten Commandments are very important and that in some sense, they should be obeyed. Most of us regard the Ten Commandments as being unique or special and yet cannot really explain why they must be so regarded. That is, we all heard about the Ten Commandments but why do we regard them more than the other laws in the Bible? For example, should we not obey the laws concerning how a man is to regard his own brother’s wife should his brother die (Levirate Marriage, see Deut. 25:5ff.)? After all, it is something God commanded. If we say that it pertains only to Israel, then could not the same be said of the Ten Commandments since the preface clearly has their deliverance in mind?
Another sad fact complicates the matter. Though many speak of the Ten Commandments, these same people cannot tell you what those Ten Commandments are. In short, most Christians tend to believe that the Ten Commandments are important and relevant but only a few of them can actually recount them.
The divines developed the topic of “moral law” before explaining its teaching on the Ten Commandments. These Ten Commandments are actually part of God’s moral law. The general idea of the moral law leads us to the specific moral laws of the Ten Commandments.
The LC answers, “The moral law is summarily comprehended in the ten commandments…” That is, the God’s moral law finds its summary teaching in the Ten Commandments. They are not the complete and exhaustive teaching of the moral law but its summary. Thomas Vincent says the commandments contain “the sum and chief heads of the law.” Ezekiel Hopkins suggests that the Bible is “the Statute-Book of God’s Kingdom” in which is “the whole body of the heavenly law…” Then he adds, “And the Decalogue, or Ten Commandments, is a summary or brief epitome of those laws…”
If we continued to study the “moral law,” we would eventually be compelled to become more specific. For example, we can speak about how our country is governed by laws. Some political parties believe we are bound to those laws while another group may take it lightly. Those are important issues. But in the end, those laws of our country must become concrete and specific. Where are these laws to be found?
The same question about the “moral law” can be asked. Where do we find this moral law? They can be found in summary form in the Ten Commandments. In fact, Vos argues, “Rightly interpreted, they include every moral duty enjoined by God.” There is a reason for this kind of thinking. If the Ten Commandments serve as a summary teaching of God’s moral law, then all moral duties could find their connection to one of the Ten Commandments by direct application, by inference, etc. Though his statement may be difficult to prove from each moral commandment of the Bible, yet his is a reasonable conclusion.
Uniquely Given by God
When the Jews compiled the law from the Bible, they counted 248 to be positive prescriptions and 365 to be negative. Yet the Ten Commandments stood out. In Deut. 10:4, Moses said, “And he wrote on the tablets, in the same writing as before, the Ten Commandments that the LORD had spoken to you on the mountain out of the midst of the fire on the day of the assembly. And the LORD gave them to me.” What we learn from Moses at this point is that the first and possibly the second set of tablets were written by God Himself (Deut. 10:3; Exodus 34:1, 4, 8). So the LC correctly states that the Ten Commandments “were delivered by the voice of God upon Mount Sinai, and written by him in two tables of stone; and are recorded in the twentieth chapter of Exodus.”
Only the Ten Commandments were written by God’s finger (“the two tablets of the testimony, tablets of stone, written with the finger of God” Ex. 31:18). This point is clearly stated in Ex. 32:16, “The tablets were the work of God, and the writing was the writing of God, engraved on the tablets.” These commandments were unique because of the way God gave them to His people.
Furthermore, these commandments are called the “Ten Words” (hence Decalogue [tou\ß de÷ka lo/gouß], Ex. 34:28; Deut. 4:13; 10:4). In fact, the Ten Words seem to distinguish itself from words like commandments, statutes, and regulations in the OT. That is, only these ten are called “words” (debarim). Douglas Stuart states explicitly that “nothing in Exodus 20 is described as ‘commandment’ or ‘law’ or the like.” They are also deemed to be “the words of the covenant” (ty$îrV;bAh yâérVbî;d) (Ex. 34:28) or “his covenant” as in Deut. 4:13: “And he declared to you his covenant, which he commanded you to perform, that is, the Ten Commandments, and he wrote them on two tablets of stone.” For that reason, they were kept in the “ark of the covenant.”
Additionally, the Ten Words came to Israel in the most frightening manner (“thunder and the flashes of lightning and the sound of the trumpet and the mountain smoking” Ex. 20:18). They were entering into a covenant with God and these Words served as the terms of that covenant. This manner of delivery was calculated to engender holy fear. The great Ezekiel Hopkins put it like this:
The wisdom of God designed it so, on purpose to possess the people with the greater reverence of it; and to awaken in their souls a due respect to those old despised dictates of their natures, when they should see the same laws revived and invigorated with so much circumstance and terror: for, indeed, the Decalogue is not so much the enacting of any new law, as a reviving of the old by a more solemn proclamation.
So the Ten Commandments clearly stood out in Israel’s history. They were not routine “laws” but unique in their role in God’s people’s lives. One commentator offers an interesting and helpful comparison:
If the American legal corpus is used as an analogy, it could be said that the ten “words” of Exod 20 are somewhat like the Constitution of the United States (legally binding in a most basic, foundational way but more than a mere set of individual laws) and the laws that follow (cf. 21:1, “These are the laws you are to set before them”) somewhat analogous to the various sections of federal law dealing with all sorts of particular matters that have been enacted legislatively over time. The one group is absolutely “constitutional” or “foundational”; the other is specifically regulatory, following from the principles articulated in the more basic “constitution.”
But Israel quickly broke the covenant almost as soon they received it. So Moses threw them (Ex. 32:19) and they broke. When Moses was recounting these events in Deuteronomy, we learn something profound and significant about the second set of tablets (which replaced the broken ones). As Peter Craigie observed, “The shattering of the first tablets symbolized the breaking of the covenant relationship because of Israel’s sin in making the calf. The second writing of the law and the gift of the tablets is indicative of the graciousness of God and the response of God to the intercession of Moses.” Yes, they broke it but God restored it and continued to maintain the covenant.
The Ten Commandments played a significant role in Israel’s history. The prophets used the Ten Commandments to rebuke Israel. “The prophets of Israel did not appeal to the law of Moses in only general terms. More specifically, each of the original Ten Commandments that summarize God’s law are applied to their contemporaries.” Surely, their placement in the ark of the covenant indicated their unique status. It was common for ANE rulers to deposit the copy of the covenant before the shrine of their deity. So the Ten Commandments served a unique role in the lives of God’s people.
The catechism further adds, “The four first commandments containing our duty to God, and the other six our duty to man.” Jesus said, “You shall love the Lord your God with all your heart and with all your soul and with all your mind. This is the great and first commandment. And a second is like it: You shall love your neighbor as yourself. On these two commandments depend all the Law and the Prophets.” (Mt. 22:37-40) Jesus is joining Deut. 6:5 (“Love the LORD your God with all your heart and with all your soul and with all your strength”) and Lev. 19:18b (“love your neighbor as yourself ”). These two commandments served as the perfect summary of the Ten Commandments. The first one focuses on man’s duty to God (the first four commandments – vertical) and the second on our duties to man (the last six commandments – horizontal).
Jesus crystalized the Ten Commandments in terms of Deut. 6:5 and Lev. 19:18b. We can all see how Jesus’ two commandments can serve as the perfect distillation of the Ten Words. We also notice the use of individual commandments in the NT (some, not all). Paul appeals to the fifth commandment (Eph. 6:1-3) and Jesus lists some of the commandments in Luke 18:20 (the rich ruler). The Ten Commandments did not die in the Old Testament; they continue on in the New Covenant.
The least we can do is actually to know what the Ten Commandments are. If you think you have kept most of them, then you will need to study the next question in the LC which will help you to correctly interpret those commandments.
 Derived from the Latin levir (husband’s brother).
 Cf. Michael Horton, The Law of Perfect Freedom (Chicago: Moody Publishers, 1993), 18-20.
 Thomas Vincent, The Shorter Catechism Explained From Scripture (1674; repr., Carlisle, PA: The Banner of Truth Trust, 1980), 113.
 Ezekiel Hopkins, The Works of Ezekiel Hopkins, 3 vols. (Morgan, PA: Soli Deo Gloria, 1997), 1:237.
 Robert West, The 10 Commandments Then and Now (Uhrichsville, OH: Barbour, 2013).
 Cf. Mark Rooker, The Ten Commandments: Ethics for the Twenty-First Century, NAC Studies in Bible & Theology (Nashville: B&H Academic, 2010), 3. However, Jesus does call them “commandments” in Luke 18:20.
 Douglas K. Stuart, Exodus, The New American Commentary (Nashville: Broadman & Holman, 2006), 440. Cf. also T. Desmond Alexander, From Paradise to the Promised Land: An Introduction to the Pentateuch, 3rd ed. (Grand Rapids: Baker Academic, 2012), 211 who makes a similar point (argued differently).
 Ezekiel Hopkins, The Works of Ezekiel Hopkins, 3 vols. (Morgan, PA: Soli Deo Gloria, 1997), 1:239.
 Douglas K. Stuart, Exodus, The New American Commentary (Nashville: Broadman & Holman, 2006), 440-441.
 Peter C. Craigie, The Book of Deuteronomy (NICOT; Grand Rapids: Eerdmans, 1976), 199-200.
 Cf. O. Palmer Robertson, The Christ of the Prophets (Phillipsburg: P & R, 2004), 143ff.
 Robertson, The Christ of the Prophets, 149.
 Cf. Rooker, The Ten Commandments, 4-6. I believe the two tablets were copies representing the two members of the covenant parties.