An essential distinctive of Reformed ethics is that it must spell out its proper relationship to the Reformed doctrine and theology of sanctification. This relationship is essential if Reformed ethics is going to truly characterize the life of the redeemed covenant people of God. If Reformed ethics is going to be only a system to look at from a distance or if it is going to be a cold, analytical study, it does not need to be tied to sanctification. But if it is going to define what must be and truly is the walk of the people of God by grace through faith alone, then it must include the doctrine of sanctification.

It is all too easy to downplay this necessary relationship. There is, after all, a certain distance between the two. They do belong in different departments. The doctrine of sanctification belongs to the department of theology proper. It has its proper place in a book of systematic theology or Reformed dogmatics. On the other hand, ethics is not a subdivision of theology proper, but belongs to practical theology. In a large divinity school, the department of theology has professors who teach the doctrines of sanctification. A department of ethics is likely to be found in a completely different building.

But if this is going to be a Reformed divinity school, a tunnel or bridge must be constructed between the office of sanctification and the office of ethics. A Reformed work on ethics must be fully informed by the doctrine of sanctification. It must be made perfectly clear that Reformed ethics is strictly impossible without the Reformed doctrine of sanctification. The doctrine of sanctification alone can explain how the regenerated child of God is truly an ethical creature, equipped to do what God’s law requires, and doing it.

Pride also makes it easy to set aside the relationship between ethics and sanctification. While it is true that pride is opposed to both the truths of sanctification and ethics, it will try to find a hiding place. In the interest of such a hiding place, pride may readily grant sanctification by faith alone without works. But it will work very hard to separate ethics from sanctification in order to find independence from God. So in sanctification everything may be ascribed to God alone. However, in ethics man must have his due because of his willingness to do or his doing of the good works of the law. God may sanctify him, but man himself must do the law of God.

There are several reasons that this relationship between ethics and sanctification must be prominent. The first reason is that for Reformed ethics to be what it is supposed to be, living and prospering in the lives of Reformed believers, it must be wholly powered by the Holy Spirit alone. Reformed ethics cannot be just a system set out in the Bible. It must be a system expressing itself really and concretely in the lives of God’s covenant people.

A second reason is closely related. Reformed ethics honors Christ as both the ethical power and perfect pattern of this ethical system living in believers. They can be and are ethical creatures because Christ renews them after his image, conforming them to him.

A third reason is that only the wondrous grace of sanctification can properly maintain the biblical ethic. 

This third reason is powerfully demonstrated in the history of apostasy. Apostate ethics is a horrifying spectacle. Apostasy has an ethical system. Divorce for any reason and remarriage after divorce are judged ethical by churches. The LGBTQ movement is not only to be tolerated, but it is also Christian and holy to support it. Opposition is simply bigotry that must be condemned and disciplined as unethical. Selfishness in marital and familial abandonment is encouraged as the holy pursuit of self-fulfillment. Churches and denominations are prolific in their support of anarchist movements, all in the name of biblical justice. Liberation theology is resurrected as social justice. In short, cut apart from the sovereign grace of sanctification, ethics must falter and fail as a system. First, it will center on outward appearances. Ultimately, it will oppose true holiness in every form. Observance of God’s law without grace must ultimately turn to anarchy.

Sanctification protects the biblical system of ethics by maintaining the heart as the center of all ethical conduct, and that heart as governed by the effectual grace of God in Jesus Christ.

Only in the light of the truth of sanctification can ethics truly be a comprehensive system of Christian conduct and behavior. It is broad in its scope. It covers the believer’s entire life. It covers the church universal. As scripture identifies one law for the whole church through the whole world and in every age, so must the one biblical system of ethics be proper to every member of that church. Reformed ethics is also comprehensive in its depth. It demands a consistency between outward conduct and inward life. It has no room for hypocrisy. It has no room for virtue projected or signaled. Its source must be the regenerated heart. Outward, formal behavior without and apart from a renewed heart is likened to whitened sepulchers, beautiful on the outside but within filled with dead men’s bones.

The consistency between outward conduct and inner thought and desire is a prominent feature of the law of God itself. There are the ten commandments, but there is also the summary of the law. While the ten commandments address outward conduct, the summary of the law spoken by Christ identifies that law with the inward virtue of love. The tenth commandment requires the heart to be free of covetousness. As the apostles and prophets applied the law of God, they called not only for reform of outward conduct, but also constantly addressed the heart. In the word of the Lord, they constantly denied any virtue to outward performance, but addressed obedience as a matter that had to proceed from the heart. Repentance and true sorrow over sin were the constant demands they inculcated. They never encouraged mere reform of outward character.

Reformed ethics also makes clear that this comprehensive system of biblical ethics has a definite and proper direction to it, a definite spiritual, moral direction. Out of the heart flow the issues of life. Out of the heart the man speaks. A good tree bears good fruit. This is the teaching of the Heidelberg Catechism. As the third section is marked by the words “Of Thankfulness,” it explains how the child of God shall show his gratitude to God for his deliverance, the third thing he must know to live and die happily in the comfort of belonging to Jesus. Lord’s Day 33 defines good works as “only those which proceed from a true faith.” Lord’s Day 24 speaks in the same way: “it is impossible that those who are implanted into Christ by a true faith should not bring forth fruits of thankfulness.”

The Reformed doctrine of sanctification makes this direction clear. The work of grace in the elect sinner begins with regeneration in his heart. His regeneration is fundamentally his entrance into the kingdom of God. Regeneration is his essential newness and goodness in the kingdom of God that are the fountain of his entire life and walk as a Christian, a life and walk that demand their full, glorious end in the perfection of heaven. But it is also that life that must spread throughout the believer’s nature with all its newness. It must permeate his inner faculties and run along through to the outward members, to bring the regenerated child of God into the way of holiness and obedience in a life full of good works. The tree is made good to bring forth good fruit.

Sanctification thus works neither contrary to the human nature nor above the human nature. It works both upon the human nature and in the human nature, so that the believer’s nature works by the power of grace alone to produce all manner of good. Salvation is by grace alone, and that salvation includes the glorious wonder of divine sanctification.

Sanctification alone makes man into a proper ethical creature. It gives him eyes to see the wonderful perfection of the law of God. It gives him ears that delight to hear the commandments of God’s law. It gives him a heart that not only inclines to hear, but also delights to obey. It gives him also the proper coordination of heart, eyes, lips, and hands to be obedient to God in all sorts of good works. True conversion leads to a life of good works. The people of God strive to put off the old man and put on the new man. No longer do they walk in sin. They turn from sin to walk in paths of righteousness for the sake of the name of their God.

This is the work of God that is beautifully expressed in Paul’s prayer for the church at Thessalonica. “The very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ” (1 Thess. 5:23). It is only this understanding of sanctification that enables God’s people to see how the good works they do lead them to the fountain of those good works, their eternal election by God. “Elect according to the foreknowledge of God the Father, through sanctification of the Spirit, unto obedience and sprinkling of the blood of Jesus Christ” (1 Pet. 1:2).

This proper operation and direction of sanctification for Reformed ethics is most clearly demonstrated in Romans 12:1–2: “I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service. And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.” This passage represents the priesthood of believers in the ethical reality of their sanctification.

The distinct power of this passage is that it is the first point of transition from the doctrinal portion of the epistle, comprising the first eleven chapters, to the practical portion of the epistle. All the instruction in consecrated living from Romans 12:3 to the end of the epistle is the implication of these first two verses of Romans 12. The remainder of the epistle details in what ways the church carries out the exhortation of Romans 12:1–2. It is how its members present their “bodies a living sacrifice, holy, acceptable unto God.” It is how they are “not conformed to this world: but…transformed by the renewing of your mind.”

These verses powerfully display the regenerated and sanctified minds of believers. The proper system of Reformed, biblical ethics has its presence in their minds. Reformed ethics never portrays the believer as a cold machine that mindlessly stamps out good works day after day. It does not simply move the fingers and lips to do and speak well independently of heart and mind. Reformed ethics begins with the heart and works through the mind into the actual performance of the law of liberty. The law written on the heart according to the new covenant brings its strength into the mind. The mind apprehends the law of God as the proper instrument for framing and driving the believer’s entire nature to the glory of the God who has redeemed him from sin and death.

The Reformed believer is blessed to come to the exhortation of Romans 12:1–2 with his mind already filled with the glorious doxology of the last verses of Romans 11. Having finished with the glorious doctrine of sovereign and unconditional double predestination, the doxology extols “the depth of the riches both of the wisdom and knowledge of God” (v. 33). The chapter ends with the all-embracing words, “For of him, and through him, and to him, are all things: to whom be glory for ever. Amen” (v. 36). This doxology is given to fill the believer with the substance of his life of consecration to God. Of God and through God, he has received his blessed salvation. Therefore, to God must be all things, including the believer’s whole life, a life lived in all its fullness to the glory of God.

Those same mercies from God are the ground for the beseeching word of Romans 12:1.

With their minds the members of Christ’s church are called to present their bodies as living sacrifices. This sacrifice is a holy sacrifice and acceptable to God by the blood of Christ. This sacrifice is called “your reasonable service.” The Christian’s “reasonable service” is the activity of his consecrated mind following after God’s law and actively seeking every opportunity that presents itself in order to show his love for God. He thinks upon that law, from its root of love to its points of application brought out in scripture. He thinks about his abilities and gifts. He sees them as a stewardship given him through the grace of Christ and thus to be consecrated to the “reasonable service” of his Lord. He considers the opportunities opening before him every day. He applies his mind to discern how he might best use them to serve his blessed Redeemer. He gladly fills those opportunities with concrete expressions of loving service to his Savior, showing grateful returns of ardent love to him who first loved him so much.

That ethical life of the mind is further described in the second verse of Romans 12 in two ways. First, the mind is identified as the central place of the transformed life of the believer. “Be ye transformed by the renewing of your mind.” The mind is no longer to be conformed to its old patterns and ways, those of the old man of sin. The believer may no longer be “conformed to this world.” He must instead be transformed. The old ethical pattern of sin and ungodliness must be consciously and deliberately rejected with the mind. The mind is to be consciously and deliberately renewed by comparison to the law of God. “Wherewithal shall a young man cleanse his way? by taking heed thereto according to thy word” (Ps. 119:9).

The second way is found in the last half of the verse, the purpose of “the renewing of your mind.” That purpose is to “prove what is that good, and acceptable, and perfect, will of God.” The object of the believer’s proving is the will of God, that is, the law of God. With his mind he is to understand that will of God as it covers all of his life. He is to understand its regulative nature. Then he is to put it to use. He must use it as a guide for his heart, his mind, and his body. It must form and direct his desires, thoughts, words, and deeds. Afterward he is meant to reflect on the ways in which his entire life bears that stamp and impress of God’s law, coming to the definite conclusion that, indeed, the will of God is “good, and acceptable, and perfect.”

Reformed ethics wondrously defines the will of God that is to be proved. As the will of God is divine and divinely revealed, so it is “good, and acceptable, and perfect.” It is the beauty of Reformed ethics to bring out that beautiful and wondrous perfection of the law of God. But Reformed ethics does not end there. Reformed ethics gloriously manifests itself in the execution of the Christian’s office as priest. It describes both what the Christian must be and do as priest and what he is and does as priest. Reformed ethics describes the way in which the believer does “prove what is that good, and acceptable, and perfect, will of God.” Because “of him, and through him, and to him, are all things: to whom be glory for ever. Amen.”