One of the problems that Protestants face is the question of subjective assurance. If persons can be sure they have been converted, how do they gain assurance? The answer is simple enough, but easy to lose sight of when you consider the moral imperatives attending the Christian religion. The result is that some want to rest their assurance on evidences of improvement, and transfer their confidence from the promises of God to their own behavior: this is called legalism. Legalism is not the only result, there is also what is called antinomianism which excuses people from a life corresponding to their Christian profession. Assurance is gained by not examining oneself, in other words: not worrying and being happy.
The Marrow of Modern Divinity by Edward Fisher addresses these two problems within the framework of Covenant Theology. Even if you’re not a Covenant Theologian, it is an interesting and ingenious system. It may even be that you do not understand these doctrines clearly in any system, though I hope you do. The advantage of the system is that once you’ve mastered it, it remains clear. Why a system? Because how else will you have coherent doctrine? If you don’t have a system, you will have contradictory interpretation. Our interpretations of Scripture don’t just come out right thanks to our natural sincerity and random ability to do things correctly. Instead, they have to be painstakingly elaborated over a long time and require the input of many people. This is because what God reveals is complex and because there is a lot of it, never mind the fact that we have little or no ability produce, no way to guarantee, and without a system really lack means to evaluate random spontaneously good results.
But what I want to do is explain how it works.
The antinomian claims there is no longer any relationship of the believer to the law. Christ, after all, has abolished the law and we live under grace. The antinomian rejects the notion of specifically Christian behavior: salvation is free, don’t criticize me. The legalist, on the other hand, says that you can’t claim to be a Christian without exhibiting lawful behavior. A legalist does not have to believe the ten commandments are still to be observed, he just has to believe that God expects you to do certain things in order to live, to intimate that you are somehow accepted on the basis of your own merit.
Scripture is clear, nobody will ever be saved by any merits other than those of Jesus Christ. Christ alone, Christ exclusively, Christ entirely. If you do not believe that, you are not a protestant. And even if you are a Christian and not a protestant, you will have to count on some confusion allowing you to get through. Anyway, it is not Christian to teach that conversion will not change your life. The work of God in a human soul is mysterious, but Jesus Christ expects it to yield fruit.
The solution that Covenant Theology offers requires both the covenant of works and the covenant of grace. The CW, remember, is what God expects of mankind before the fall: do this and you shall live. The idea is that it stands for natural law; you would have had to honor your parents and refrain from murder even had there been no fall. The CW was broken by Adam, and according to the terms of the covenant, we must die. The Mosaic Law serves to condemn in that it participates and is an instance of this covenant. It is still useful for that purpose to this day, useful to condemn, for legal humiliation, to bring men to despair of their own effort. It shows human kind that we are all born and live and will unaided die under the covenant of works. The CW can be resumed in this: do this and you shall live.
Christ, however, the second Adam, did and fulfilled that covenant. Because he did, those who are joined to him can die to the law as it is a covenant of works and can live now under a new covenant, the covenant of grace. Since nobody can be under both covenants, you are either under the covenant of works or through faith in Christ are under the covenant of grace. And if you are under the covenant of grace, you can’t go back to the covenant of works. The Mosaic Law, however, can instance both, and so we see it also participates in this new covenant, but not as a covenant of works. As a covenant of grace the terms are: live, and do this, rather than do this and live. Christ has purchased life, and under the terms of the covenant of grace offers it to all who will believe. There is nothing to do to gain life but to believe. Having life, being joined by faith to Christ and being dead to the covenant of works, how do we live? By the law of Christ, the law of God which is holy, just and good. Under the covenant of grace you have the third use of the law, as the guide to living the Christian life.
So the antinomian is answered: we do not throw out the law, but instead by faith in Christ we repent our transgressions of the law and desire to fulfill it. God works in us to will it and more. He works in us to do, not for merit, but because it lies in the direction that our living under a new covenant takes. The legalist is also answered who browbeats the Christian with an ill-tempered God who is always standing over him nagging him about all his inadequacies and not witnessing (in the parable of the talents, the chap with only one talent is a legalist, poor sod). The antidote to legalism is to know God’s goodness and free grace in Christ, and how the Lordship of Christ is not a new tyrannical oppression, but a freedom to desire and pursue what God wants, what is wholesome and right. The sorrow of sin is not a sorrow of despair, or of owing once again. There are duties, but the duties are not a burden that can’t be borne. They are the law of Christ, his easy yoke and light burden, since it keeps us usefully plowing and is a voluntary burden. These old duties are faced with a new attitude, and are duties for which new resources make us both eager and able. We are Christ’s cheerful fellow oxen, in his own metaphor, and there is nothing any creature can desire that is more. We can make progress in these duties having escaped the terms of the covenant of works and enjoying the terms of the covenant of grace.
I did that without mentioning the kingdom, didn’t I? And I enjoyed the book. You can also look at Sinclair Ferguson’s The Whole Christ if you want something more dumbed down, though not quite as dumbed down as this post.