A sin of commission is taking action we should not. This can be in deed, thought, or something we say. Conversely, a sin of omission is when we don't take action we should.
What does the Bible say about sins of commission?
Sin is when we act out of harmony with God and His desires and intentions for our lives. Both sins of commission or omission can be intentional or unintentional. The Bible tells us that all people sin and even one sin separates us from God, and without God we cannot have life everlasting. We earn death by our sin, but God offers us life through His Son, Jesus (Romans 6:23).
The Holy Spirit will help us know and follow God's desires for us, but we cannot completely stop sinning. However, we can have peace with God and peace of mind when we put our faith in Jesus Christ and trust that His death and resurrection is our substitute punishment for our sin and the power to resurrect us (Colossians 2:14; Romans 6:6). We are told in 2 Corinthians 5:21 that Jesus is perfect but He took our place so that we could be righteous before God.
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.
There are many examples of sins of commission and omission in the Bible. Adam and Eve committed a sin of commission when they did what they were told not to do by eating the fruit of a tree they were forbidden to eat from (Genesis 2:16–17). King David committed adultery and murder (2 Samuel 11). Because of His great love, God remained in relationship with them and others. However, the consequences of their sin remained.
When we take action 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. "But what comes out of the mouth proceeds from the heart, and this defiles a person. For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false witness, slander" (Matthew 15:18-19).
David shows us how to react when we sin. In Psalm 51, he repents of his sin in sorrow, but also with a belief in God's mercy. David admits his sin, turns to God, and asks for His work to continue in him. "Create in me a clean heart, O God, and renew a right spirit within me. Cast me not away from your presence, and take not your Holy Spirit from me. Restore to me the joy of your salvation, and uphold me with a willing spirit" (Psalm 51:10–12).
As Christians, we will sin like David did, and we can react to that sin with confidence that God hears our confession, remains in relationship with us, and will help us to live in accordance with His desires. 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."
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Truth about Sin