How do we know Christ's atoning work is effective?

The effectiveness of Christ's atonement can be seen in its comprehensive fulfillment of God's law and justice. In 1 Samuel 6, the Ark being returned with a trespass offering foreshadows Christ's perfect sacrifice for our sins. Jesus bore our sins as the ultimate offering, taking upon Himself the punishment we deserve. Romans 5:1 assures us that, through faith in Christ, we are justified and have peace with God, proving that His sacrifice met the divine requirements. Thus, believers can rest assured in the sufficiency of Christ's finished work.