Some notes on Sin

Thomas Aquinas writes:

. . . sin is broadly used to mean any failure of activity, natural or designed, to reach its goal . . . . But the meaning of sin proper to morals is of cuplable failure of will to reach a due goal because it is drawn toward an unsuitable one.

Essentially, sin is "missing the mark", failing to measure up to a proper standard. The "mark", in this case, is God's Law. Biblically speaking, "Everyone who sins breaks the law; in fact, sin is lawlessness" (1 John 3:4, NIV) or in the King James, "for sin is the transgression of the law."

So, our duty to God is live our lives in such as way as to avoid clashing with His will. Put positively: Our best interest is served when we are in line His Law. Life should be lived in such a way as to avoid sin, to "hit the mark" as it were. The trick of it is, of course, learning what the mark is. I like how John Wesley's mother explained it (Letter, June 8, 1725):

Take this rule: whatever weakens your reason, impairs the tenderness of your conscience, obscures your sense of God, or takes off your relish of spiritual things; in short, whatever increases the strength and authority of your body over your mind, that thing is sin to you, however innocent it may be in itself.

For a more in depth look at a biblical view of sin, check out "What is Sin?" by Tony Warren.