What is the Moral Law? I recently watched a podcast that said those who believe in the Moral Law seem to say that the Decalogue is written word-for-word in the hearts of the New Testament believers (as if they are robots!). But, are they correct in saying that? Or, are they merely creating a caricature of the view they were trying to debunk? Let’s see how it is defined by the confession, catechisms, and some reformed theologians.
1689 LBCF 10.5,
“The moral law does for ever bind all, as well justified persons as others, to the obedience thereof, and that not only in regard of the matter contained in it, but also in respect of the authority of God the Creator, who gave it; neither does Christ in the Gospel any way dissolve, but much strengthen this obligation.”
The Baptist Catechism, Question #46
Where is the moral law summarily comprehended?
The moral law is summarily comprehended in the ten commandments.¹
¹ Deuteronomy 10:4; Matthew 19:17
The Baptist Catechism, Question #47
What is the sum of the ten commandments?
The sum of the ten commandments is, to love the Lord our God, with all our heart, with all our soul, with all our strength, and with all our mind; and our neighbour as ourselves.¹
¹ Matthew 22:37–40
The Westminster Larger Catechism, Question #98
Where is the moral law summarily comprehended?
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;¹ 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.²
¹ Deuteronomy 10:4; Exodus 34:1–4
² Matthew 22:37–40
The Westminster Confession of Faith 19.7
7. Neither are the forementioned uses of the law contrary to the grace of the gospel, but do sweetly comply with it:a the Spirit of Christ subduing and enabling the will of man to do that freely and cheerfully which the will of God, revealed in the law, requireth to be done.b a. Gal 3:21. • b. Ezek 36:27; Heb 8:10 with Jer 31:33.
Richard Muller,
"[S]pecifically and predominantly, the Decalogus, or Ten Commandments; also called the lex Mosaica . . ., as distinct from the lex ceremonialis . . . and the lex civilis, or civil law. The lex moralis, which is primarily intended to regulate morals, is known to the synderesis [i.e., the innate habit of understanding basic principles of moral law] and is the basis of the acts of conscientia [i.e., conscience–the application of the innate habit above]. In substance, the lex moralis is identical with the lex naturalis . . . but, unlike the natural law, it is given by revelation in a form which is clearer and fuller than that otherwise known to the reason."
Richard Barcellos,
"…the moral law is summarily comprehended in the Decalogue, not exhausted by it. Though the formal promulgation of the Decalogue had a unique redemptive-historical context and use, it is nothing other than the natural law incorporated into the Mosaic covenant in a new form."
John Murray,
"The Ten Commandments, it will surely be admitted, furnish the core of the biblical ethic. When we apply the biblico-theological method to the study of Scripture it will be seen that the Ten Commandments as promulgated at Sinai were but the concrete and practical form of enunciating principles which did not then for the first time come to have relevance but were relevant from the beginning. And it will also be seen that, as they did not begin to have relevance at Sinai, so they did not cease to have relevance when the Sinaitic economy had passed away. It is biblico-theological study that demonstrates that these commandments embody principles which belong to the order which God established for man at the beginning, as also to the order of redemption. In other words, we discover that they belong to the organism of divine revelation respecting God’s will for man." - As quoted by Richard Barcellos from Going Beyond the Five points, p. 48
Here’s a helpful section from Philip S. Ross’ From the Finger of God: The Biblical and Theological Basis for the Threefold Division of the Law, Chapter II: What Would Moses Think?
Bostons thought is representative when he states that the ‘law of the ten commandments, being the natural law, was written on Adams heart on his creation., .it became the law of works, whereof the ten commandments were, and are still the matter.’ This natural law can never expire or determine’—it ‘is obligatory in all possible states of the creature, in earth, heaven or hell’.10 According to Fairbairn, we misunderstand Boston if we suppose he meant ‘that there was either any formal promulgation of a moral law to Adam, or that the Decalogue as embodying this law, was in precise form internally communicated by some special revelation to him’.11 This, however, may itself be a misunderstanding, for when Evangelista expounds this view to Nomista in The Marrow of Modern Divinity (upon which Boston is commenting), Nomista asks, ‘But, sir, how could the law of the ten commandments be the matter of this covenant of works, when they were not written, as you know, till the time of Moses?’12 Evanglista responds that this was so, for Adam was created in the image of God.13Nomista ‘cannot but marvel’ at this, yet Evangelista sharply rebuffs him and tells of a ‘learned writer’ who said, Adam heard as much in the garden, as Israel did at Sinai; but only in fewer words and without thunder.’
Finally, here are from the two great theologians: John Calvin and John Owen,
Now that inward law, which we have above described as written, even engraved, upon the hearts of all, in a sense asserts the very same things that are to be learned from the two Tables. For our conscience does not allow us to sleep a perpetual insensible sleep without being an inner witness and monitor of what we owe God, without holding before us the difference between good and evil and thus accusing us when we fail in our duty. But man is so shrouded in the darkness of errors that he hardly begins to grasp through this natural law what worship is acceptable to God. Surely he is very far removed from a true estimate of it. Besides this, he is so puffed up with haughtiness and ambition, and so blinded by self-love, that he is as yet unable to look upon himself and, as it were, to descend within himself, that he may humble and abase himself and confess his own miserable condition. Accordingly (because it is necessary both for our dullness and for our arrogance), the Lord has provided us with a written law to give us a clearer witness of what was too obscure in the natural law, shake off our listlessness, and strike more vigorously our mind and memory." (John Calvin, Institutes, 2.8.1)
"But in itself [the Decalogue], and materially considered, it was wholly, and in all the preceptive parts of it, absolutely moral. Some, indeed, of the precepts of it, as the first, fourth, and fifth, have either prefaces, enlargements, or additions, which belonged peculiarly to the then present and future state of that church in the land of Canaan; but these especial applications of it unto them change not the nature of its commands or precepts, which are all moral, and, as far as they are esteemed to belong to the Decalogue, are unquestionably acknowledged so to be." (Owen, Works, XVIII:366 as quoted by Richard Barcellos in JOHN OWEN AND NEW COVENANT THEOLOGY
Notice the phrases “summarily comprehended”, “in fewer words and without thunder”, “the concrete and practical form of enunciating principles”, “materially considered” and “in a sense asserts the very same things.” These writers in no way affirm that the Decalogue is written word-for-word in the hearts of the New Covenant believers.
From the quotations above we can say that the Decalogue is identical in essence to the Natural/Moral law not its word-for-word transcription in the hearts of men created in the image of God. The very substance of the Ten Commandments/Decalogue is the Moral Law that forever binds all men because of its transcendental and transcovenantal nature coming from the Giver of the law Himself.
Quotations from Richard Muller and Richard Barcellos are from this article: How the “uses of the law . . . sweetly comply with . . . the grace of the Gospel ” (2LCF 19.7)