Sin is when we act out of harmony with God and His desires and intentions for our lives. A sin of commission is taking action we should not in deed, thought, or word. Conversely, a sin of omission is when we don't take action we should. Both types of sin can be intentional, as when Adam and Eve disobeyed God’s command (Genesis 2:16-17, Genesis 3), or unintentional, as proven by the Mosaic Laws about sacrifices for unintentional sin (Leviticus 4:2) The Bible shows that sins of commission can have serious consequences, separating us from God and affecting our relationships, our conscience, and our spiritual growth. An example is David’s adulterous affair with Bathsheba and his arrangements to have her husband killed (2 Samuel 11). Though David repented and God forgave him, the consequences of David’s sin were dissension in His household (2 Samuel 12:10). Yet even when we actively choose to do what is wrong, God’s grace is available to us through Jesus, offering forgiveness and restoration (1 John 1:9). We are called to acknowledge our wrongdoing, repent, and turn back toward Him (1 John 1:9), allowing the Holy Spirit to guide our thoughts, words, and actions (Galatians 5:16). By doing so, we can find forgiveness and experience God’s peace again, living according to God’s purposes and in a way that reflects Him to a world that desperately needs Him (Matthew 5:16).
When we break a law, such as speeding, we owe the maker of the law, the government, a fine to pay for our misdeed. It doesn't matter if we knew the speed limit or were unaware. We still broke the law. We cannot pay God for our sins, but Jesus can, and did, for us. When we act outside of God's intentions for us, we commit sins of commission. When we fail to do what God intends, we commit sins of omission.
As Christians, we will still sin because we are not fully in a perfected state. But, we can respond to that sin by confidently knowing that God hears our confession, remains in relationship with us, and will help us to live in accordance with His desires. We can repent and return to seeking after God. Philippians 4:4–8 offers us wise counsel in how to live that way: "Rejoice in the Lord always; again I will say, rejoice. Let your reasonableness be known to everyone. The Lord is at hand; do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus. Finally, brothers, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things." Even when we commit sins of commission—actively doing what is against God’s will—we can still turn back to Him. By confessing these sins, relying on the Holy Spirit’s guidance, and focusing on what is true, pure, and good, we can live in a way that reflects Christ’s love and live according to God’s purposes.