Question: What is Sin?
Answer: Sin is any want of conformity to the law of God, or transgression of it. 'Sin is the transgression of the law' (1 John 3:4). Of sin in general:
 Sin is a violation or transgression. The Latin word, transgredior, to transgress, signifies to go beyond one's bounds. The moral law is to keep us within the bounds of duty. Sin is going beyond our bounds.
 The law of God is not the law of an inferior prince, but of Jehovah, who gives laws as well to angels as men; it is a law that is just, and holy, and good (Rom. 7:12). It is just, there is nothing in it unequal; holy, nothing in it impure; good, nothing in it prejudicial. So that there is no reason to break this law, no more than for a beast, that is in a fat pasture, to break over the hedge, or to leap into a barren heath or quagmire.
I shall show what a heinous and execrable thing sin is. It is malorum colluvies, the complication of all evil; it is the spirits of mischief distilled. The Scripture calls it the 'accursed thing' (Josh. 7:13). It is compared to the venom of serpents, and the stench of sepulchres. The apostle uses this expression of sin, 'Out of measure sinful' (Rom. 7:13); or, as it is in the Greek, 'Hyperbolically sinful.' The devil would paint sin with the vermilion colour of pleasure and profit, that he may make it look fair; but I shall pull off the paint that you may see its ugly face. We are apt to have slight thoughts of sin, and say to it, as Lot of Zoar, 'Is it not a little one' (Gen. 19:20)? But that you may see how great an evil sin is, consider these four things:
I. The origin of sin, from whence it comes. It fetches its pedigree from hell; sin is of the devil. 'He that committeth sin is of the devil' (1 John 3:8). Satan was the first actor of sin, and the first tempter to sin. Sin is the devil's first-born.
II. Sin is evil in the nature of it.
 It is a defiling thing. Sin is not only a defection, but a pollution. It is to the soul as rust is to gold, as a stain to beauty. It makes the soul red with guilt, and black with filth. Sin in Scripture is compared to a 'menstruous cloth' (Is. 30:22), and to a 'plague-sore' (1 Kings 8:38). Joshua's filthy garments, in which he stood before the angel, were nothing but a type and hieroglyphic of sin (Zech. 3:3). Sin has blotted God's image, and stained the orient brightness of the soul. It makes God loathe a sinner (Zech. 11:8); and when a sinner sees his sin, he loathes himself (Ezek. 20:43). Sin drops poison on our holy things, it infects our prayers. The high priest was to make atonement for sin on the altar, to typify that our holiest services need Christ to make an atonement for them (Ex. 29:36). Duties of religion in themselves are good, but sin corrupts them, as the purest water is polluted by running through muddy ground. If the leper, under the law, had touched the altar, the altar would not have cleansed him, but he would have defiled the altar. The apostle calls sin, 'Filthiness of flesh and spirit' (2 Cor. 7:1). Sin stamps the devil's image on a man. Malice is the devil's eye, hypocrisy his cloven foot. It turns a man into a devil. 'Have not I chosen you twelve, and one of you is a devil' (John 6:70)?
 Sin is grieving God's Spirit. 'Grieve not the Holy Spirit of God' (Eph. 4:30). To grieve is more than to anger.
How can the Spirit be said to be grieved? For, seeing he is God, he cannot be subject to any passion.
This is spoken metaphorically. Sin is said to grieve the Spirit; because it is an injury offered to the Spirit, and he takes it unkindly, and, as it were, lays it to heart. And is it not much thus to grieve the Spirit? The Holy Ghost descended in the likeness of a dove; and sin makes this blessed dove mourn. Were it only an angel, we should not grieve him, much less the Spirit of God. Is it not sad to grieve our Comforter?
 Sin is an act of contumacy against God; a walking antipodes to heaven. 'If ye will walk contrary to me' (Lev. 26:27).
A sinner tramples upon God's law, crosses his will, does all he can to affront, yea, to spite God. The Hebrew word for sin, Pasha, signifies rebellion; there is the heart of a rebel in every sin. 'We will do whatsoever proceedeth out of our own mouth, to burn incense to the queen of heaven' (Jer. 44:17). Sin strikes at the very Deity; Peccatum est Deicidium [Sin is God's would-be murderer] . Sin would not only unthrone God, but un-God him. If the sinner could help it, God would no longer be God.
 Sin is an act of disingenuity and unkindness. God feeds the sinner, keeps off evils from him, bemiracles him with mercy; but the sinner not only forgets God's mercies, but abuses them. He is the worse for mercy; like Absalom, who, as soon as David had kissed him, and taken him into favour, plotted treason against him (2 Sam. 15:10). Like the mule, who kicks the dam after she has given it milk. 'Is this thy kindness to thy friend' (2 Sam. 16:17)? God may upbraid the sinner. 'I have given thee,' he may say, 'thy health, strength, and estate; but thou requitest me evil for good, thou woundest me with my own mercies; is this thy kindness to thy friend? Did I give thee life to sin? Did I give thee wages to serve the devil?'
 Sin is a disease. 'The whole head is sick' (Is. 1:5). Some are sick of pride, others of lust, others of envy. Sin has distempered the intellectual part, it is a leprosy in the head, it has poisoned the vitals. 'Their conscience is defiled' (Titus 1:15). It is with a sinner as with a sick patient, his palate is distempered, the sweetest things taste bitter to him. The word which is sweeter than the honey-comb' (Ps. 19:10), tastes bitter to him, he puts 'sweet for bitter' (Is. 5:20). This is a disease, and nothing can cure this disease but the blood of the Physician.
 Sin is an irrational thing. It makes a man act not only wickedly, but foolishly. It is absurd and irrational to prefer the less before the greater; the pleasures of life, before the rivers of pleasures at God's right-hand for evermore. Is it not irrational to lose heaven for the satisfying or indulging of lust? As Lysimachus, who, for a draught of water, lost a kingdom. Is it not irrational to gratify an enemy? In sin we do so. When lust or rash anger burns in the soul, Satan warms himself at this fire. Men's sins feast the devil.
 Sin is a painful thing. It costs men much labour to pursue their sins. How do they tire themselves in doing the devil's drudgery! 'They weary themselves to commit iniquity' (Jer. 9:5). What pains did Judas take to bring about his treason! He goes to the high priest, and then after to the band of soldiers, and then back again to the garden. Chrysostom says, 'Virtue is easier than vice.' It is more pains to some to follow their sins, than to others to worship their God. While the sinner travails with his sin, in sorrow he brings forth; which is called 'serving divers lusts' (Titus 3:3). Not enjoy, but serve. Why so? Because not only of the slavery in sin, but the hard labour; it is 'serving divers lusts.' Many a man goes to hell in the sweat of his brow.
 Sin is the only thing God has an antipathy against. God does not hate a man because he is poor, or despised in the world; as you do not hate your friend because he is sick; but that which draws forth the keenness of God's hatred, is sin. 'Oh, do not this abominable thing that I hate' (Jer. 44:4). And sure, if the sinner dies under God's hatred, he cannot be admitted into the celestial mansions. Will God let the man live with him whom he hates? God will never lay a viper in his bosom. The feathers of the eagle will not mix with the feathers of other fowls; so God will not mix and incorporate with a sinner. Till sin be removed, there is no coming where God is.
III. See the evil of sin, in the price paid for it. It cost the blood of God to expiate it. 'O man,' says Augustine, 'consider the greatness of thy sin, by the greatness of the price paid for sin.' All the princes on earth, or angels in heaven, could not satisfy for sin; only Christ. Nay, Christ's active obedience was not enough to make atonement for sin, but he must suffer upon the cross; for, without blood is no remission (Heb. 9:22). Oh what an accursed thing is sin, that Christ should die for it! The evil of sin is not so much seen in that one thousand are damned for it, as that Christ died for it.
IV. Sin is evil in its effects.
 Sin has degraded us of our honour. Reuben by incest lost his dignity; and though he was the first-born, he could not excel (Gen. 49:4). God made us in his own image, a little lower than the angels; but sin has debased us. Before Adam sinned, he was like a herald that has his coat of arms upon him: all reverence him, because he carries the king's coat of arms; but let this coat be pulled off, and he is despised, no man regards him. Sin has done this, it has plucked off our coat of innocence, and now it has debased us, and turned our glory into shame. 'And there shall stand up a vile person' (Dan. 11:21). This was spoken of Antiochus Epiphanes, who was a king, and his name signifies illustrious; yet sin degraded him, he was a vile person.
 Sin disquiets the peace of the soul. Whatever defiles, disturbs. As poison tortures the bowels, corrupts the blood, so sin does the soul (Is. 57:21). Sin breeds a trembling at the heart; it creates fears, and there is 'torment in fear' (1 John 4:18). Sin makes sad convulsions in the conscience. Judas was so terrified with guilt and horror, that he hanged himself to quiet his conscience. And is not he like to be ill cured, that throws himself into hell for ease?
 Sin produces all temporal evil. 'Jerusalem has grievously sinned, therefore she is removed' (Lam. 1:8). It is the Trojan horse, that has sword and famine, and pestilence, in its belly. Sin is a coal, that not only blacks, but burns. Sin creates all our troubles; it puts gravel into our bread, wormwood in our cup. Sin rots the name, consumes the estate, buries relations. Sin shoots the flying roll of God's curses into a family and kingdom (Zech. 5:4). It is reported of Phocas, that having built a wall of mighty strength about his city, there was a voice heard, 'Sin is within the city, and that will throw down the wall.'
 Sin unrepented of brings final damnation. The canker that breeds in the rose is the cause of its perishing; and corruptions that breed in men's souls are the cause of their damning. Sin, without repentance, brings the second death, that is mors sine morte, Bernard 'a death always dying' (Rev. 20:14). Sin's pleasure will turn to sorrow at last; like the book the prophet did eat, sweet in the mouth, but bitter in the belly (Ezek. 3:3; Rev. 10:9). Sin brings the wrath of God, and what bucket or engines can quench that fire? 'Where the worm never dies, and the fire is not quenched' (Mark 9:44).
Use one: See how deadly an evil sin is, and how strange is it that any one should love it! 'How long will ye love vanity' (Ps. 4:2)? 'Who look to other gods, and love flagons of wine' (Hos. 3:1). Sin is a dish men cannot forbear, though it makes them sick. Who would pour rose-water into a kennel? What pity is it so sweet an affection as love should be poured upon so filthy a thing as sin! Sin brings a sting in the conscience, a curse in the estate; yet men love it. A sinner is the greatest self-denier; for his sin he will deny himself a part in heaven.
Use two: Do anything rather than sin. Oh, hate sin! There is more evil in the least sin than in the greatest bodily evils that can befall us. The ermine rather chooses to die than defile her beautiful skin. There is more evil in a drop of sin than in a sea of affliction. Affliction is but like a rent in a coat, sin a prick at the heart. In affliction there is aliquid mellis, some good: in this lion there is some honey to be found. 'It is good for me that I was afflicted' (Ps. 129:71). Utile est anima si in hac area mundi flagellis trituretur corpus. Augustine. 'Affliction is God's flail to thresh off our husks; not to consume, but to refine.' There is no good in sin; it is the spirit and quintessence of evil. Sin is worse than hell; for the pains of hell are a burden to the creature only; but sin is a burden to God. 'I am pressed under your iniquities, as a cart is pressed under the sheaves' (Amos 2:13).
Use three: Is sin so great an evil? Then how thankful should you be to God, if he has taken away your sin! 'I have caused thy iniquity to pass from thee' (Zech. 3:4). If you had a disease on your body, plague or dropsy, how thankful would you be to have it taken away! Much more to have sin taken away. God takes away the guilt of sin by pardoning grace, and the power of sin by mortifying grace. Oh be thankful that this sickness is 'not unto death;' that God has changed your nature, and, by grafting you into Christ, made you partake of the sweetness of that olive; that sin, though it live, does not reign, but the elder serves the younger; sin the elder serves grace the younger.