How do we know that Christ's atonement is effective?

The efficacy of Christ's atonement is rooted in several significant truths. First, His perfect obedience is seen throughout His life, culminating in His death on the cross as a sinless sacrifice (2 Corinthians 5:21). The prophetic declarations in Isaiah concerning Christ’s suffering provide foundational evidence that He fulfills the role of the suffering servant, emphasizing that His death was not an accident but a predetermined measure of divine justice and mercy. Furthermore, the New Testament writers testify to the transformative power of His atoning sacrifice that not only bears our sins but also leads to our reconciliation with God (Romans 5:10). This illustrates the complete and sufficient nature of Christ's work, ensuring that He effectively secured our salvation.