Sin is any falling short of God's perfect standard, and at its root it is rebellion against God Himself. It entered the world through Adam's disobedience, it spreads to every person, and it brings death and separation. The good news is that where sin abounded, grace abounded much more in Christ.
Not a summary of these passages: the passages themselves. Read them, then come back to the study below.
The study
What the Scripture says
1
Sin is lawlessness and falling short
Sin is lawlessness: transgression of God's revealed will. All have sinned and fall short of the glory of God. Whoever knows the right thing to do and does not do it, for him it is sin: sin is both what we do against God and what we refuse to do for Him.
Everyone who sins also commits lawlessness. Sin is lawlessness.Whosoever committeth sin transgresseth also the law: for sin is the transgression of the law.
To him therefore who knows to do good, and doesn’t do it, to him it is sin.Therefore to him that knoweth to do good, and doeth it not, to him it is sin.
Through one man sin entered into the world, and death through sin, and so death passed to all men, because all sinned. The woman saw that the tree was desirable, and she took it and gave it to her husband, and the world broke.
Therefore as sin entered into the world through one man, and death through sin; and so death passed to all men, because all sinned.Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned:
When the woman saw that the tree was good for food, and that it was a delight to the eyes, and that the tree was to be desired to make one wise, she took some of its fruit, and ate; and she gave some to her husband with her, and he ate it, too. Their eyes were opened, and they both knew that they were naked. They sewed fig leaves together, and made coverings for themselves.And when the woman saw that the tree was good for food, and that it was pleasant to the eyes, and a tree to be desired to make one wise, she took of the fruit thereof, and did eat, and gave also unto her husband with her; and he did eat. And the eyes of them both were opened, and they knew that they were naked; and they sewed fig leaves together, and made themselves aprons.
For as through the one man’s disobedience many were made sinners, even so through the obedience of the one, many will be made righteous.For as by one man’s disobedience many were made sinners, so by the obedience of one shall many be made righteous.
The wages of sin is death. Your iniquities have separated you from your God, and your sins have hidden his face from you. You were dead in your trespasses and sins, children of wrath. Sin is not a small thing; it is cosmic rebellion with cosmic cost.
For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord.For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
but your iniquities have separated between you and your God, and your sins have hidden his face from you, so that he will not hear.But your iniquities have separated between you and your God, and your sins have hid his face from you, that he will not hear.
You were made alive when you were dead in transgressions and sins, in which you once walked according to the course of this world, according to the prince of the power of the air, the spirit who now works in the children of disobedience; among whom we also all once lived in the lust of our flesh, doing the desires of the flesh and of the mind, and were by nature children of wrath, even as the rest.And you hath he quickened, who were dead in trespasses and sins; Wherein in time past ye walked according to the course of this world, according to the prince of the power of the air, the spirit that now worketh in the children of disobedience: Among whom also we all had our conversation in times past in the lusts of our flesh, fulfilling the desires of the flesh and of the mind; and were by nature the children of wrath, even as others.
Where sin increased, grace abounded all the more, so that grace might reign through righteousness to eternal life through Jesus Christ our Lord. If we confess our sins, he is faithful and righteous to forgive us the sins and to cleanse us from all unrighteousness. There is no condemnation for those in Christ.
The law came in besides, that the trespass might abound; but where sin abounded, grace abounded more exceedingly; that as sin reigned in death, even so grace might reign through righteousness to eternal life through Jesus Christ our Lord.Moreover the law entered, that the offence might abound. But where sin abounded, grace did much more abound: That as sin hath reigned unto death, even so might grace reign through righteousness unto eternal life by Jesus Christ our Lord.
If we confess our sins, he is faithful and righteous to forgive us the sins, and to cleanse us from all unrighteousness.If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.
There is therefore now no condemnation to those who are in Christ Jesus, who don’t walk according to the flesh, but according to the Spirit.There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit.
Therefore as sin entered into the world through one man, and death through sin; and so death passed to all men, because all sinned.Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned:
For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord.For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
Everyone who sins also commits lawlessness. Sin is lawlessness.Whosoever committeth sin transgresseth also the law: for sin is the transgression of the law.