How do we know that God forgives all sins?

David declares in Psalm 103 that God has forgiven all our iniquities, a promise that rests on the truth of redemptive grace provided in Jesus Christ. This forgiveness is comprehensive and unconditional for those whom God has called to Himself. The assurance of complete forgiveness reflects God's character as a just God and a Savior. This doctrine is foundational for understanding salvation in Christian theology, showing that Christ bore the sins of His people, no longer counting those sins against them, which allows believers to rejoice in their freedom from guilt and condemnation.