"For we are His workmanship, created in Christ Jesus unto good works, which God hath before ordained that we should walk in them."--Ephes. ii. 10.
Good works are the ripe fruit from the tree which God has planted in sanctification.
In the saint there is life; from that life workings proceed; and those workings are either good or evil. Hence good works are not added to sanctification for mere effect, but belong to it: The discussion of sanctification is not complete without the discussion of Good Works.
Whatever man may be, works always proceed from him; and since works are never neutral, but either conform or do not conform to the divine law, it follows that every man's works are either good or evil, actual sins (Peccata actualia)or good works. In fact, every life has its own energizing. Without it it is no life. Properly speaking, life in the saint does not proceed from sanctification, but sanctification lends it tone, color, and character.
In a garden where the conditions are all equal, and there is
the same soil, the same fertilizer, etc., different fruit-trees are planted.
Evidently, the working that makes the trees grow is from the soil; for if
planted in the garret, they will not grow. But the cause that produces peaches
on one tree and grapes on another is not in the soil, but in the trees. Hence
we must distinguish the working itself from the shade, the tone, the
character, the peculiar property which that working assumes. The wind that
produces sweetest music from the Eolian harp, by blowing through a broken
window-pane produces doleful sounds. It is one operation but different effects:
In the meadow next to the tender clover grows the poisonous wolf's, milk. Yet
both lift their little heads from the same soil and drink in the same air,
sunlight, and rain. Altho the vital energy is the 
same, the
difference in the seeds causes differences in the, plants, and opposite
effects.
The same applies to the garden of the soul, where the human life is in full activity. But that same human life produces a base act to-day and a heroic act to-morrow. There is but one working, but the colors vary, it may be white or black, dark or light.
And this we find, that in the garden of the soul all spontaneous growth is a growth of weeds; while the seed which God has planted produces precious fruit. The effects of sanctification are evident. It causes sweet waters to flow from a bitter fountain. It lends to every operation its own quality and property, and gives it a direction which works for good. And thus good works proceed from the man lost in himself.
Of course, in the root, this apparently identical working is twofold. One springs from the old nature, the other from the new; the one from the natural, the other from the supernatural. But since this distinction was discussed at large in the chapter on Regeneration, we treat it now simply from the unity of the person:
Altho we heartily agree with the Confession, "That a regenerated person has in him a twofold life: the one temporal and corporeal, that which he has from the first birth and is common to all men; the other spiritual and heavenly, which is given him in the second birth, and which is peculiar to God's elect" (art. 35); yet this does not affect the unity of the person, nor does it alter the fact that the operations of both the old and the new life are my operations. If I divide my person, and take the natural and the supernatural each by itself, then there is no sanctification at all; for the corrupt life of my old nature is not sanctified, but crucified, dead, and buried; and my heavenly, spiritual, and regenerated life can not be sanctified inasmuch as it never was sinful nor ever can be. Hence in sanctification we have to consider life from the viewpoint of the unity and indivisibility of the person. The man who was first wedded to the corrupt nature, and who is now wedded to the new man, was then evil and is now to become good; wherefore his life must receive the holy desire, inclination, and disposition. And then only it is possible for it to produce good works.
A work is good when it is conformable to the divine law.
1. The first point is that God alone possesses the right to determine what is good or evil.
Man also can acquire this discernment, but only by being taught of God. But as soon as he presumes himself to determine the difference between good and evil, He violates the divine majesty and God's inalienable right to be God. Not one man, nor many men, nor all men and angels together may do this. It does not belong to them. It is the eternal prerogative of the Almighty Creator of heaven and earth. He alone determines good and evil, for every creature, for time and eternity.
That which He demands of each life shall be the law of that life, of all that belongs to it, and under all circumstances; a law in which all the divine ordinances are comprehended. His law, tho its principles are briefly comprehended in the Ten Commandments, rises from these ten stems in branches and boughs broad and dense, and forms in its completeness one immeasurable roof of leaves which overshadows the entire human family in all its variegations.
Hence there is not the remotest chance here to compromise. God's will and law are absolute; rule over all; are binding in every domain, and can never be repealed. And where, in the delicate works of a watch, the thousandth part of a millimeter is allowed to a wheel for variation, in the divine law such play is unthinkable. The law of God brooks not even the deviation of a hair's breadth, nor of any infinitesimal fraction thereof.
Hence a good work does not signify a work merely not evil; nor a work containing some good, or simply passable; nor a work whose good intention is evident. But a good work is nothing else and nothing less than a good work. And it is not good unless it is absolutely good, i.e., in all its parts equally conformable to the divine will and law. A peach is not half a pear an& half a grape, but absolutely a peach; so a good work is not merely passable, partly well intentioned, but absolutely conformable to what God has determined to be good with regard to that work.
1t is readily seen that unless sanctification were adapted to
enable man to perform such a work, he would never accomplish it. As it is the
peculiar habit of a peach-tree, through its ascending life, to impart to the
fruit the flavor of the peach, and of the grape-vine to give to its fruit the
flavor of the grape, so it is the peculiar quality of the soul sanctified in
principle to impart to its fruit the flavor of the law. Sanctification
does not merely inspire the soul with a desire for something higher, but it
imparts to it 
such a disposition, tone, shade, flavor, and
character that it, yields to the divine law. And the law puts its impress upon
the soul. The soul's aspiration is no more a vague ideal, but it has a positive
pleasure in and a desire and love for all, the commandments of God. And, since
sanctification engrafts the law upon the soul, it is possible that the working
which follows should be conformable to the law.
We say "possible," for from his own sad experience God's child knows that it is possible to be otherwise, and that many summers come and go without reaping from his branches any noticeable harvest for the glory of God.
2. This brings us to the second point. A good work must be of faith.
Sanctification itself is not of faith. It has nothing to do with faith. It is wrought by God Himself. What could faith then accomplish in this respect?
But it is different with reference to good works; for they must be our good works. Man is and should be passive in all other respects, but not in his work. Work is the end of one's passive condition. To work and to be passive are opposites. To imagine that, work can be passive or actively passive is like imagining that a circle is square, that ink is white, that water is dry. Wherefore the Heidelberg Catechism rightly asks: "Why must we still do, good works?"
Hence there can be no good work unless it is wrought by ourselves. And every representation as tho man did not perform good works, but that the Holy Spirit performs them in him and in his place, is to subvert the Gospel and to wrest the Scripture.
The work of Christ is vicarious, that of the Holy Spirit is not: He works in man, but not in his place. And however extensive His work may be in us, being wrought independently of us, it can never be counted as our own. Christ died and rose from the dead for us and independently of us. But the Holy Spirit can not draw fruit from the tree except our, ego executes the work.
But--and this should be emphasized--our ego can not execute it
except" the work is wrought in us with power." The inward, higher life does not
act like the sap in the, vine, for this enters the vine naturally. But
the working of the holy life is different. Altho a holy disposition is
implanted, God's child does not produce any good fruit of himself. Altho well
furnished and well equipped, 
if left to himself he produces nothing; not a single
good work, however small.
The most skilful diamond-cutter, tho supplied with the best tools, can not furnish the smallest diamond rose except the proprietor of the establishment gives him the diamond, the steam-power in his tools, and even the gas-light upon his hands. In like manner it is impossible for the most excellent among God's children, tho their souls be well equipped, to furnish a single good work, except the Proprietor of the holy-art establishment gives them the material, the power, and the light.
Hence the content and entire form of every good work is not of man, but of the Holy Ghost, so that when it is finished we owe thanks to God, and not He to us. In every man who performs a good work He works both to will and to do.
But when the Holy Spirit has furnished everything necessary, then one thing is still lacking, viz., that the saint do it and make the work his own. And this is the wonderful act of faith.
There is not one good work which God has not prepared before, that we should walk in it; and this is why it is not wrought until we walk in it. The Lord says to Ezekiel, "I will cause you to walk in my statutes," but the Lord does not cause us to walk therein until we actually walk in them. We shall neither be carried nor be wheeled into them.' This would have no value before the divine Majesty; that would be no art. Even we can wheel the cripple in his carriage; but the art of making him to walk, yea, even to leap as a hart, is not human, but worthy of God alone. And we may not allow this to be taken from Him by a sickly mysticism, and thus rob God of this glory.
To say, as many do, that the Lord carries His children imperceptibly into good paths, and that this constitutes their good works, is to despise holy things. No one should touch the honor of our God; and we may not rest until the pure doctrine burns again from the candlestick: that the power of God is manifest in the fact that He causes the cripple to walk, to run, and do leap as a hart.
And this is the act of faith, i.e., that wonderful act
of the soul of casting itself into the deep, knowing that it shall fall into
the everlasting arms of mercy, tho it is utterly unable to see. Faith in this
respect is to agree with the divine will; to accept the good 
work which
God has prepared for us, as our own; to appropriate to ourselves what God gives
us.
An awkward schoolboy has to make a speech before a strange audience. It is a difficult task, and he does not even know how to begin. All his own efforts are useless. Then his father calls him and says: "If you commit this little speech which I have prepared, and recite it without missing a word, it will be a success." And the boy obeys. There is nothing of himself--it is all his father's work; he merely believes that what his father has prepared for him is good. And in this confidence he goes before the strange audience, delivers his father's composition, and succeeds. However, the writing of the speech did not end the matter, and it could not be ended until the boy had done his part. When God has prepared the good work for us, the matter is not ended until we do what God has prepared for us.
Coming home the boy does not proudly ask a reward, but with gratitude he embraces his father for his love and faithfulness. Having obtained success, God's children are profoundly thankful for their Father's excellent help; and they acknowledge that they owe it all to Him. And if He is pleased to give them a reward, it is not because they have deserved it; for if it were a question of desert, the children would have to give everything to the Father! But it is merely a reward of love for the future support of their faith.