What is the sin nature?

The Bible teaches that all human beings are born with a crucial flaw in their natures, and that flaw is sin. In Ephesians 2:1 Paul tells us, "You were dead in your transgressions and sins." The reason for our spiritually dead condition is the sin of the first man, Adam. According to Genesis 1:26, Adam was made in the image of God. He was a free moral agent. Of his own choice, Adam sinned (disobeyed God), and the entire human race was plunged into sin. (See Gen. 3 and Rom. 5:12‑21 for the account and the implications of what is commonly known as the Fall.)

How could Adam's disobedience plunge all of us into sin? Theologians from all the major branches of the Christian Church agree that Adam acted as "federal head of the human race." That is, he represented all of us, and his initial act of sin had consequences for everyone, for all time. In his letter to the Romans, Paul sums it up by saying, "Sin entered the world through one man, and death through sin, and in this way death came to all men, because all sinned" (Rom. 5:12). Because Adam was our representative, God counted us guilty because of his sin."

At first glance, Romans 5:12 sounds like an unfair judgment on everyone who lived after Adam. But is it? All of us know by experience that we do not live up to all that we know we should do (or not do) in relationship to God and our fellowman. Scripture teaches that we are all descended from Adam, and because we are part of Adam's family (the entire human race), we all have Adam's nature - a sinful heart. "The heart," writes Jeremiah, "is deceitful above all things and beyond cure. Who can understand it?" Jer. 17:9.

To start with, the Lord Jesus reminds them of the fact that every man is evil by nature, a fact which has been so since the fall. God had said already at the time of Noah that the thought of man's heart is evil from his youth (Gen. 8:21). David reveals a deep understanding of God's assessment of men as he says in Psalm 51:5: 'Behold, I was shapen in iniquity; and in sin did my mother conceive me.' But when men judged the only sinless one on the cross of Calvary as a criminal the total depravity of human nature was revealed in its entirety. The nature of the 'old man', that is of the flesh, is incorrigible, and this is why God gives new and everlasting life and a new nature to every one who believes.

Every creature of God has its own nature, and of God’s creatures on earth man has a very distinctive nature that sets him apart from all others. Alas, sin has entered into the nature of man and has brought in all the ruin, decay, disease and death that we see all around. Scripture relates plainly that this was brought about by the sin of Adam and Eve, and that every child of Adam has inherited his sinful nature. Adam’s sin made him a guilty creature, and put him at a distance from God, but it also introduced into his nature an evil principle, sin, that had not been there before. The long centuries of man’s life upon earth have demonstrated the utter ruin of human nature, but the cross of Christ has not only shown that it is incorrigible, but there God condemned the sin that controlled, and formed part of, man’s nature as away from God (Rom. 8:3).

In the first part of Romans, what we have done - our sins, is the chief subject, and Christ delivered for them in grace, so that they are gone for ever for those who believe. But there is another question to be settled - not only what we have done, but what we are. These two questions are raised in Genesis 3. God said to Eve, in verse 13, "What is this that thou hast done?" and to Adam (v. 9), "Where art thou?" God has, so to speak, asked the question in the first part of the epistle, "What hast thou done?" And when everything is brought to light, and all that we have done is nothing but sin, in His love and grace He has given His Son to put it away. This is up to Romans 5:11. Now the question of what we are by nature is taken up, "Where art thou?" Then, how God delivers us, not only from our sins, but from what we are as children of Adam, from our sinful nature - which is a much deeper thing. Why do we commit sins? Because we are all born into this world with a corrupt, fallen nature, as in Psalm 51: "Behold, I was shapen in iniquity; and in sin did my mother conceive me." Yes, a little infant is born in sin; and how soon the sinful nature begins to manifest itself! How soon does a child begin to have a will of its own, to show temper and to be disobedient! The testimony of Scripture is plain as to this evil nature, that it is utterly bad, and not only so, but unimprovable (a fact which many of us are slow to learn).

From the middle (ver. 11) of the fifth chapter of Romans, where we read of the believer rejoicing, joying, boasting, exulting in God through our Lord Jesus Christ, the apostle takes up the subject of the sin within the believer. We may commit sins. If we do so it is because something exists within us from which these sins proceed. From our natural birth we possess an irrepressible disposition to sin. This evil tendency is inherited from our first parents, Adam and Eve. It was “by one man sin entered into the world, and death by sin” (ver. 12). With the single word “sin,” God points His finger to the seat of the trouble in the believer. Sin is in the heart. From that root, all varieties of evil fruit spring. The fountain is poisoned at its source. This is true, not of one person only, but of all men alike. All share in the possession of sin and in its consequence and penalty, death. And although a believer's sinful acts are forgiven and he himself justified, there remains within him the inherited disposition to sin.

But the first man is of the earth, "earthy" (1 Cor. 15:47): and, since his fall, his pursuits, habits, thoughts, desires and character have been centred in himself. God is not in all his thoughts; and having come under the influence of Satan, he hates God, and lives in self-will and sin. Not only was one sin put to man's account by his disobedience, but sin entered into his nature, making it a sinful nature; and he put himself at a distance from God. There was no power with man to do what was good, or to resist the evil; and he could neither regain his place in Eden nor remove from his nature the principle of sin that had entered there.

In the nature that God gave to man there is that which is lovely. Natural affection, in its purity, is most attractive; and in man's relations with his fellows, and with the creatures around him, there are expressions of natural goodness, kindness, and other traits which make relationships on earth not only tolerable, but also happy. Yet all has been vitiated by sin: even the purist of natural affections have been affected, and ruin marks all that is best in man by nature. There were lovely traits in the young ruler who told Jesus that he had observed all the commandments from his youth up, and we read, "Then Jesus beholding him loved him" (Mark 10:21). Beneath the ruin of fallen nature there can still be seen the lovely traits of the nature that God gave to Adam unfallen; but all lies in ruin and sin, and man of the first order can never please God.

Here we have the positive activity of evil, the actual energy of self-will. For, be it remembered, sin is doing our own will in whatever line that will may travel, whatever form it may assume. It may present itself in the shape of the grossest moral depravity or it may array itself in the garb of a cultivated and refined taste, but it is self-will all the while, and self-will is sin. It may be only like the acorn, the mere seed, but the acorn contains the wide spreading oak. Thus the heart of the newly born infant is a little seed-plot in which may be found the germ of every sin that ever was committed in the world. True, each seed may not germinate or bring forth fruit, but the seed is there and only needs circumstances or influences to unfold it.

Now the statement of this may be rejected, and God’s revelation of it utterly refused by the very heart which sin has rendered deceitful; but the fact remains, and finds abundant proof on all hands. What is bred in the bone comes out in the flesh, and sin, self-will, enmity against God, is the underlying principle of our fallen nature. We are both sinful and guilty.

Is not this what souls really want, to be forgiven their sins, and to be delivered from sin? It is a bitter and evil thing to forsake the living and true God; yet this is what man has done and is doing. He is hewing out to himself broken cisterns that can hold no water; he seeks happiness, and, if he gets any signs, puts all into a broken pitcher. But sin stings like a viper in the end. It may be found out with sorrow and regret, when power against it is wanting. It is a sorrowful thing to see sin mastering a soul. Man is a slave of his own lusts, as well as of Satan. Sin is degrading, and men feel it, yet for all that there is no power. Man is lying under it. A child may have been carefully guarded by a loving parent from the indulgence of its natural propensities; but what sorrow for the parent, when the guard is removed, to see them break out in full energy, the will at work, and no power against sin!

Unconverted persons know they love the things that are not of God. Whence does it all come? From a heart that is contrary to God — a nature at enmity with God. The heart loves the things that suit its own lusts. We all by nature turn away from God, and all are alike in this, those who have been most restrained by natural checks and the most vicious. There may be least care about it in the least vicious, because a very vicious man would be glad to be out of the scrape. When the prodigal left his father's house, he was as wicked as afterwards, he was glad to get away from his father and to do his own will. There may be a desire to please the father from natural affection; but there is the wish to have the opportunity to do one's own will, and this was all the prodigal wanted. What can we say of such a heart as that? The prodigal son was as guilty, though not so degraded, when he crossed his father's threshold as when eating husks in the far country.

“By one man sin entered into the world.” Innocence existed in one man — Adam. God made Adam free from evil; without the knowledge of sin. This was the starting point of man's existence upon earth — a life in its moral characteristics totally distinct from our present life. But Adam preferring disobedience to obedience, and exercising his will, his nature became evil, and thereupon the character of the fountain of human life became changed. Innocence disappeared from the earth, and sin entered the world. This is the origin of our sinful nature which we received through our parents, and with which we were born. We trace the river from this present day to the past generation — we follow it back further and further till we reach its source — and we find that every age has produced a nature which is sinful.