Luther, along with the Orthodox Lutherans who followed him, identified truly good works with the keeping of the Law, that is, obeying the Ten Commandments, by believers. While imperfect in this life, good works done in faith are indeed possible. Because of Christ, God overlooks the imperfection of our good works, and in this life and in the next rewards them solely by His grace. While Christ has fulfilled the Law completely for us through His pure and holy life and His bitter sufferings and death, we begin to fulfill the Law in this life as we are enabled by the Spirit working through the Gospel. Nevertheless, our perfection in body and soul will only be possible in the “life of the world to come.” Here’s Luther:
I. We ought first to know that there are no good works except those which God has commanded, even as there is no sin except that which God has forbidden. Therefore whoever wishes to know and to do good works needs nothing else than to know God’s commandments. Thus Christ says, Matthew xix, “If thou wilt enter into life, keep the commandments.” And when the young man asks Him, Matthew xix, what he shall do that he may inherit eternal life, Christ sets before him naught else but the Ten Commandments. Accordingly, we must learn how to distinguish among good works from the Commandments of God, and not from the appearance, the magnitude, or the number of the works themselves, nor from the judgment of men or of human law or custom, as we see has been done and still is done, because we are blind and despise the divine Commandments…
Faith, as the chief work, and no other work, has given us the name of “believers on Christ.” For all other works a heathen, a Jew, a Turk, a sinner, may also do; but to trust firmly that he pleases God, is possible only for a Christian who is enlightened and strengthened by grace…
So a Christian who lives in this confidence toward God, a knows all things, can do all things, undertakes all things that are to be done, and does everything cheerfully and freely; not that he may gather many merits and good works, but because it is a pleasure for him to please God thereby, and he serves God purely for nothing, content that his service pleases God.
Martin Luther, “A Treatise on Good Works, Along With the Letter of Dedication”(1520), Christian Classics Ethereal Library, 13,14,15. (See also AE 44:23ff.)
Lutheran Orthodoxy 