1 John 3:4
Every person who practices a life of sin is also breaking [God's] law, for sin is law-breaking.
1 John 5:17
All wrongdoing is sinful, and [yet] there is a situation where [a person's] sin does not lead [him] to [spiritual] death.
Romans 3:20
This is because no human being can be considered right with God by [obeying] the requirements of a law. [Note: It is difficult to determine the exact sense in which "law" is used in these verses. It may be law generally, or the law of Moses specifically. See Bruce, pages 52-58]. For the knowledge of what sin is comes from the law of Moses.
Romans 4:15
For the law brings [God's] wrath [i.e., because of man's failure to obey it perfectly], but where there is no law, there is no [responsibility for] sin.
2 Corinthians 12:21
I am afraid that, when I come, my God will humiliate me in front of you, and I will be grieved over many [of those] who have sinned in the past without repenting of the [moral] impurity, sexual immorality and unrestrained indecency they have practiced.
Romans 7:7-13
What shall we say then? Is the law of Moses sinful? Certainly not! For I would not have known what sin was if it had not been for the law. For [example]; I would not have known [what it meant] to covet [i.e., have a strong desire for what belongs to someone else] except that the law said [Ex. 20:17], "You must not covet."
James 2:9-11
But if you show favoritism toward [certain] persons, you are committing a sin and are convicted by the law [of God] as lawbreakers.
James 5:15
And if their prayer is [offered] by faith, [God] will heal the one who is sick, and the Lord will raise him up [from his sickbed]. And if he had sinned, he will be forgiven for them [Note: This may imply that the man's sickness was the result of some sin. In any event, his forgiveness would follow his repentance].
1 John 3:8-9
[But] the person who continues to live a sinful life belongs to the devil, because the devil has continued to sin since the beginning [See Gen. 3]. For this is the reason that the Son of God came [into the world]; it was to destroy the works [i.e., the influence of] the devil [in people's lives].