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Definition and description
Of 'sin'; whether bad intentions are sins.
A sin is not only a transgression of a law, but also any contempt of the legislator. For such contempt is a breach of all his laws at once, and therefore may consist, not only in the commission of a fact, or in the speaking of words by the laws forbidden, or in the omission of what the law commandeth, but also in the intention or purpose to transgress. For the purpose to break the law is some degree of contempt of him to whom it belonged to see it executed. To be delighted in the imagination only of being possessed of another man's goods, servants, or wife, without any intention to take them from him by force or fraud, is no breach of the law, that saith, "Thou shalt not covet": nor is the pleasure a man may have in imagining or dreaming of the death of him from whose life he expecteth nothing but damage and displeasure, a sin; but the resolving to put some act in execution that tendeth thereto. For to be pleased in the fiction of that which would please a man if it were real is a passion so adherent to the nature both of man and every other living creature, as to make it a sin were to make sin of being a man. The consideration of this has made me think them too severe, both to themselves and others, that maintain that the first motions of the mind, though checked with the fear of God, be sins. But I confess it is safer to err on that hand than on the other.
Hobbes, Lev XXVII 1
Between sin and crime: all crimes are sins, but not all sins are crimes.
A crime is a sin consisting in the committing by deed or word of that which the law forbiddeth, or the omission of what it hath commanded. So that every crime is a sin; but not every sin a crime. To intend to steal or kill is a sin, though it never appear in word or fact: for God that seeth the thought of man can lay it to his charge: but till it appear by something done, or said, by which the intention may be argued by a human judge, it hath not the name of crime: which distinction the Greeks observed in the word amartema and egklema or aitia; whereof the former (which is translated sin) signifieth any swerving from the law whatsoever; but the two latter (which are translated crime) signify that sin only whereof one man may accuse another. But of intentions, which never appear by any outward act, there is no place for human accusation. In like manner the Latins by peccatum, which is sin, signify all manner of deviation from the law; but by crimen (which word they derive from cerno, which signifies to perceive) they mean only such sins as may be made appear before a judge, and therefore are not mere intentions.
Hobbes, Lev XXVII 2