If ye live after the flesh ye, shall die."--Rom. viii. 13.
Altho sin is originally and essentially a loss, a lack, and a deprivation, in its working it is a positive evil and a malignant power.
This is shown by the apostolic injunction not only to put on the new man, but also to put off the old man with his works. The well-known theologian Maccovius, commenting on this, aptly remarks: "This could not be enjoined if sin were merely a loss of light and life; for a mere lack ceases as soon as it is supplied.
If sin were merely a loss of righteousness, nothing more would be needed than its restoration, and sin would disappear. The putting off of the old man, or the 1aying down of the yoke of sin, etc., would be out of the question. The light has only to dispel the soul's darkness, and its health will be restored. But experience shows that after we are enlightened, and the Holy Spirit has entered our heart, there is still a fearful power of evil in us; and this together with the oft-repeated command not only to accept the righteousness of God which is by faith, but also to put off, to lay aside, to be separate from all that is evil, proves sin's positive character and evil power in individuals and in society, in spite of its privative character.
Hence the Church confesses that our nature has become
corrupt, which of course refers us back to the divine image. Our nature did not
disappear, nor cease to be our nature, but in its orignal features and organs
it remained the same; the divine image was not lost, not even partly lost, but
remained stamped upon every man, and will remain even in the place of eternal
destruction sin because he can not divest himself of his nature except by
annihilation. But this being impossible, he must retain it as man and in
man's nature. Wherefore Scripture teaches long after the fall that the
sinner is created after the image of God. But concerning the 
effects
of its features in the fallen human nature, the very opposite is true:
these features have totally disappeared; the ruins which remain speak at the
most only of the glory and beauty which have perished.
Hence the two meanings of the divine image should no longer be confounded. Forasmuch as it lies in our nature it will remain evermore; so far as its effects upon the quality, i.e., the condition, of our nature are concerned, it is lost. The human nature can be corrupted, but not annihilated. It can exist as nature, even tho its former attributes be lost, and replaced by opposite workings.
Our fathers discriminated between our nature's being and its well-being. In its being it remained uninjured and unharmed, i.e., it is still the real, human nature. But in its condition, i.e., in its attributes, workings, and influences, in its well-being it is wholly changed, and corrupt. Tho a poisoned insect-sting destroys the sight, yet the eye remains. So is the human nature; deprived of its luster, checked in its normal activity, internally sore and foul, yet it is the human nature.
But it is corrupted by sin. It is true man hag retained the power to think, will, and feel, besides many glorious talents and faculties, even genius sometimes; but this does not touch the corruption of his nature. Its corruption is this, that the life which should be devoted to God and animated by Him is devoted with downward tendencies to earthly things. And this reversed action has changed the whole organism of our being.
If the divine righteousness were essential, to human life, this could not be so; but it is not. According to Scripture, death is not annihilation. The sinner is dead to God, but in this very death throbs and thrills his life to Satan, to sin, and to the world: If the sinner had no sinful life, Scripture could never say, "Mortify therefore your members which are upon the earth," for it is impossible to mortify that which is dead already.
Let not similarity of sound deceive us. Human life is
indestructible. When the soul is active in conformity to the divine law,
Scripture says that the soul lives; if not, it is dead. This death is the wages
of sin. But for this reason man's nature does not cease to work, to use its
organs, to exert its influence. This is the life of our members which are in
the earth--our sinful life, the inward festering of evil in our corrupt nature;
for this reason it must be mortified. Hence since sin does not stop our nature
from 
breathing, working, feeding, but it causes these activities, which under the
sway of the divine law did run well and were full of blessing, to go wrong and
be corrupt.
The mainspring of a watch when detached from its pivot does not stop it immediately; but, being uncontrolled, it turns the wheels so rapidly as to ruin the mechanism. In some respects human nature resembles that watch. God has endowed it with power, life, and activity. Controlled by His law it worked well, and in harmony with His will. But sin deprived it of that control, and, while these powers and faculties remain, they run the wrong way, and destroy the delicate organism. If this condition lasted only for a moment, and the sinner were immediately restored to his original state, it could not lead to a positive evil. But sin lasts a long time; sixty centuries already. Its pernicious influence has its effects; a secondary disease after the primary; accumulations of sinful dregs, and increase of festering sores. The threads of our, nature's woof pull awry. Everything wrenches itself out of joint. And, since this secondary activity continues unchecked, its pernicious working becomes more and more critical.
What causes a felon? A sliver in the finger slightly checks the circulation. But the blood continues to circulate, trying to overcome the obstacle. The additional pressure against the walls of the capillaries produces more friction, and raises the temperature. The surrounding tissue swells, the delicate blood-vessels contract, the friction increases, and the boil throbs. Altho this is but the continued normal action of the circulation, yet it causes positive evil. There is a local congestion; poisonous matter inflames the healthy tissue, and the parts are thoroughly diseased.
And such is sin's course. The action of our powers continues,
but in the wrong direction. This causes disorder, and irregularities, which
inflame our nature toward evil. This sinful inflammation creates unnatural and
wicked deformations, which excite the tissues of the soul to a morbid growth,
compared by Scripture to foul matter. And from this unholy marsh poisonous
gases rise continually throughout our entire nature. Thus the whole economy is
disordered. Having run away from the divine law without discipline, body and soul
become unruly. Hence, incited by its own inherent action, it involves itself
more deeply and runs farther away from God. As a train that is derailed
destroys itself by its very speed, so does man, having left the track of the
divine law, 
compass his own rdin by the inherent impetus and
working. Nothing more is needed. Destruction results necessarily from the very
life of our nature.
Hence the sinner is without knowledge, the feelings axe perverted, the will is paralyzed, the imagination polluted, the desires are impure, and all his ways, tendencies, and outgoings are at once evil; not in our eyes, perhaps, but because everything fails to meet the demands of God, who wills that everything should meet Him at the terminus of the road, i.e., to be with Him and in Him, making His glory the final, end of all things.
And this makes many things sinful, unrighteous, and wicked that we consider fair and beautiful. Not our taste, but God's, decides what is right or wrong. He that wishes to know what that taste is, let him learn it from the law of God. That law is standard and plummet. But whatever the sinner seeks or desires to please God, he will not do this; e.g., he may be perfectly willing to hang his coat on the wall and do it gracefully, but not on the nail that God has struck in the wall of our life; everywhere else, but not there. Thus everything in him becomes evil, his entire nature corrupt, incapable of any good, inclined to all evil, yea, prone to hate God and his neighbor. The deed may not be born, but the very inclination and desire are sin.
Like the Romish and some Lutheran theologians, Dr. Böhl denies this. He teaches that there was this desire in holy Adam and even in Christ; not indulged, but held in with bit and bridle--as tho God had created man with this ravenous, animal of desire in his heart, while He endowed him at the same time with the power to restrain it. To keep this desire in constant check would have been man's greatest excellence.
But this is not according to Scripture. Nothing shows that holy Adam had any desire for the things he saw. The possibility of desire was created only by the prohibition: "Of the tree of knowledge of good and evil thou shalt not eat." And even after that we do not discover a trace of desire in him. Such eager looking at the fruit was not witnessed until Satan had inwardly incited Eve not to eat of the fruit, but through it to become like God. This is the first desire awakened in man's heart, and that only after his eye was opened to see that the tree was good for food and pleasant to the eye.
In the righteous state Adam was filled with peace, harmony,
and 
divine success; without a trace of the anxiety necessarily springing from the
task of restraining a dangerous monster. And in the, heavenly glory it will not
be an endless desire to restrain desire, but a complete deliverance from
desire; not the suction of a great deep in our bottomless heart, but all its
depths filled with, the love of God.
The commandment "Thou shalt not covet" is absolute. The Lord Jesus was a total stranger to covetousness. He never desired what God withheld. In Gethsemane's terrible dénouement He desired, yet not to receive a gift, but to retain His own, i.e., when under the curse not to be forsaken of His God.