On the Moral Law and the Law of Nature

Francis Roberts



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Being Book 3, Chapter 4, Aphorism 1, Question 6 of his

The Mystery and Marrow of the Bible: God’s Covenants with Man



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Whether the Moral Law is the Same as the Law of Nature?

I.  Yes, according to the general sum and substance of it

1.  The gentiles do the Moral Law by nature

2.  The Law of Nature requires us to love God and our neighbor

3.  The Law of Nature was contained in the holiness of Adam

4.  Adam broke the Law of Nature; Christ fulfilled the Moral Law

II.  No, according to the particulars and circumstances of it

1.  The Moral Law is more comprehensive and particular

with respect to (1) the First, (2) Second, and (3) Fourth Commandments, (4) the Judicial Laws, and (5) the Tenth Commandment

2.  The Moral Law was given as part of the Covenant of Grace; the Law of Nature was given as part of the Covenant of Works

3.  The Moral Law only binds those to whom it is revealed; the Law of Nature binds all mankind

4.  The Moral Law is a stronger bond to God as Redeemer; the Law of Nature only binds persons to God as their Creator

5.  The Moral Law was given on Mt. Sinai with many remarkable circumstances




On the Moral Law and the Law of Nature


Whether the Law Given on Mt. Sinai was the Same with the Law of Nature Written in Adam’s Heart Before the Fall, and in Some Measure Remaining Still in Man’s Heart Since the Fall?


Answer:  The identity or sameness of the Law of Nature written in Adam’s heart with the Law given on Mt. Sinai is by some taken for granted, but by others this is counted a very questionable point.  But may we not most safely and satisfactorily resolve this with a distinction?  Namely:

I.  According to the general sum and substance of the Moral Law, it seems to be the same with the Law of Nature written in Adam’s heart in Innocency.  For,

1.  The gentiles that have not the Moral Law written do by nature the things contained in the Law for substance, which shows the work of the Law written in their hearts (Rom. 2:14-15).  The imperfect relics of the Law of Nature remaining in them put them upon doing the work of the Moral Law.  Therefore, for sum and substance the Moral Law and Law of Nature are the same, thus producing one and the same effect for substance.

2.  The general sum and substance of the Moral Law is: To love God over all with all the heart, soul, mind and might, and to love our neighbors as ourselves, doing to them as we would they should do to us (Matt 22:36-41; 7:12).  And the Law of Nature required this.  Yea, the decayed light of nature even in pagans teaches thus much, as is evident by the writings of many heathens: Aristotle, Plato, Seneca, Cicero, Cato, etc. 

3.  God created man at first upright (Eccl. 7:29) and in his own image (Gen. 1:26-27).  God’s image especially and summarily consists in holiness and righteousness (Eph. 4:24).  With these Adam was principled and in these the Law of Nature was contained.  And these are the sum of the Moral Law: holiness is the sum of the first table, righteousness the sum of the second. 

4.  The same law for substance which the first Adam broke to the ruin of all his natural posterity did Christ the last Adam perfectly keep and fulfill, enduring the curse and penalty thereof to the recovery of his elected supernatural posterity.  Otherwise the remedy had not been full, proper, and pertinent to the malady.  But the first Adam broke the Law of Nature in violating that positive law about the forbidden fruit (Gen. 2-3).  And Christ the last Adam (Gal. 4:4; 3:13) kept the charge and endured the curse of the Moral Law: death.  Therefore the Moral Law and Law of Nature were the same for sum and substance.

II.  According to the particulars and circumstances of the Moral Law, it has diverse (and those considerable) differences from the Law of Nature imprinted on Adam’s heart in his creation.  For:

1.  The Moral Law is more comprehensive, having in it more particulars required and forbidden than the Law of Nature either had or needed to have.  The Moral Law comprises in it all that was in the Law of Nature, but the Law of Nature had not in it all that is in the Moral Law.

(1)  The First Commandment requires our having the Lord alone for our God in Christ by faith, walking before Him in all evangelical obedience, and, to that end, our repenting of every sin opposite to having the Lord for our God.  But the Law of Nature could require none of these things with reference to Christ as Mediator, there being in Innocency no need of a mediator. 

(2)  The Second Commandment comprises in it the whole instituted worship of God, both under the Old and New Testaments, requiring that from time to time his people should worship Him according to his revealed will.  So that all the Ceremonial Law under the Old Testament (principally typifying Christ to come afterwards), and all the evangelical ordinances of worship under the New Testament (tendering [offering] Christ as come already), are contained in the Second Commandment, and all contrary offences are forbidden.  But neither Ceremonial Laws nor New Testament ordinances, nor anything of Christ, was contained in the Law of Nature. 

(3)  The Fourth Commandment requires the sanctification of the Sabbath Day and particularly determines, as to the Jews under the Old Testament, that Sabbath to be every seventh day.  But the Law of Nature can hardly be conceived to require the sanctification of every seventh day as an holy Sabbath to God.¹  For what could there be in nature to determine upon the seventh day rather than upon any other of the six days?  How can it be infallibly evinced that God sanctified the seventh day before man’s Fall and not rather after man’s Fall.²  And seeing the Sabbath is to be sanctified especially by the solemn acts of worship according to the ordinances of the Old Testament before Christ and according to the ordinances of the New Testament since Christ, how could the Law of Nature instruct in these acts of Sabbath sanctifying which had their whole tendency to Christ?

¹ [Note that Roberts here agrees with Westminster Confession 21.7, “As it is the law of nature, that, in general, a due proportion of time be set apart for the worship of God; so, in His Word, by a positive, moral, and perpetual commandment, binding all men, in all ages, He hath particularly appointed one day in seven, for a Sabbath, to be kept holy unto Him…”]

² [Roberts gives six arguments that it is probable that Adam fell from Eden on the sixth day (the same day he was created) in Book 2, Chapter 1, Aphorism 6, Section 3, Point 3.  Thus the first Sabbath on the seventh day would have been after Adam fell into sin, was under the curse, and was kicked out of Eden.]

(4)  The second table comprised the body of those judgments or judicial laws imposed on the commonwealth of Israel. The Law of Nature could not reach to these positive laws.

(5)  The Tenth Commandment discovers lust to be sin, even the first motions or inclinations of the heart against our neighbor’s good, though not deliberately assented to by the will. But did, or does, the Law of Nature make this particular discovery?  Do heathens discover concupiscence to be sin by the Law of Nature?  Paul had the Law of Nature, yet says he had not known lust to be sin unless the Law had said, ‘Thou shalt not covet’ (Rom. 7:7). 

Thus the Moral Law in the particulars comprised therein surpasses the Law of Nature.

2.  The Moral Law was given as a Covenant of Faith³ in Christ the Mediator, revealing justification and happiness by faith in Christ (as has been already showed and will after more appear).  But the Law of Nature was given to Adam as a Covenant of Works, revealing to him justification and happiness by his own works and the perfect fulfilling of the Law.  So that in their end and scope they differ as far as two distinct kinds of covenants one from another.

³ [‘Covenant of Faith’ for Roberts means an Old Testament administration of the Covenant of Grace.]

3.  The Moral Law given on Sinai binds only the Jews under the Old Testament and Christians under the New Testament to whom it comes and is revealed.  But the Law of Nature is of universal obligation, binding all mankind, being engraven in the heart of Adam (the root of all mankind), the imperfect relics whereof remain still in all mankind, the penalty also of this broken Covenant of Works (death) lying fully upon all mankind, pagans and others, till they embrace the Covenant of Faith and Christ therein as the only all sufficient remedy.

4.  The Moral Law given on Mount Sinai imposes a further bond upon all them that have it than the Law of Nature.  The Law of Nature binds to obedience.  But the Moral Law (comprising in it the Law of Nature), binds more strongly, and is as a double bond.  The Law of Nature binds to obey God the Creator.  The Moral Law binds to obey God not only as Creator, but as Redeemer also.  So that the sins of Jews before Christ or of Christians since Christ against the Moral Law, are far more heinous and inexcusable than the sins of pagans against the Law of Nature (especially considering that these have but a very dark and imperfect rule of the Law of Nature, but those have a very clear and complete rule of the Moral Law).

5.  The Moral Law was given on Mt. Sinai with many remarkable circumstances attending the same as these eight formerly mentioned.¹  But the Law of Nature was given into Adam’s heart without any such circumstances.

¹ [In Book 3, Chapter 4, Aphorism 1, Question 3]



The End




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