What Is Sin?

Q. 14: What is sin?
Answer: Sin is any want of conformity unto, or transgression of, the law of God. (WSC)

The apostle John gave us a simple definition of sin when he said that “sin is lawlessness” (1 John 3:4). Sin is defined by the law of God. If it is not a violation of God’s law, it is not a sin. But God’s law requires perfect conformity. It is a perfect rule of righteousness, showing us what is right, revealing to us the will of God. As Paul says, the law is “holy and righteous and good” (Rom. 7:12). It is not an arbitrary law, but an expression of God’s holy character and our place in God’s design. Any departure from this law is a departure from righteousness, a deviation from our duty, a rebellion against God, and a basis for judgment.

Our catechism mentions two ways we fall short of God’s law. First, "sin is any want [lack] of conformity unto … the law of God." This lack of conformity is found in our sins of omission, not doing what the law commands. The law calls us to fulfill our duties, and failure to do our duty is sin. This lack of conformity is also found in original sin, our innate hostility against God’s law in our fallen state. It is sinful for our nature to be hostile to God, out of accord with his will. This is described in Romans 8:7, “For the mind that is set on the flesh is hostile to God, for it does not submit to God’s law; indeed, it cannot.” Sin is deeper than our actions. It also refers to our desires, our mindset, our heart. Unlawful desires that spring into our minds are sin. We ought to confess them to God and mortified them, seeking the renewal of our minds and hearts.

Second, sin is also the "transgression of the law of God." This refers to sins of commission, doing that which is forbidden. He has given us a good deal of freedom within his law, as he gave to Adam and Eve in the Garden of Eden. Yet, God has also set boundaries with his law, guardrails to our path. To violate these boundaries is sin and a manifestation of pride and a lack of faith in God. Instead, let us say with Psalm 119:32, “I will run in the way of your commandments when you enlarge my heart!” As God renews our minds and hearts by his grace, we are enabled to not merely stay on the path, but to run eagerly in the good and righteous way of his commandments.