How do we know Christ's sacrifice is enough for our sins?

The sufficiency of Christ's sacrifice is evidenced by its acceptance by God. After offering His sacrifice, Christ sat down at the right hand of the Father, signaling that His work is finished (Hebrews 10:12). This contrasts with the Old Testament priests who could never sit down because their work was never complete—sacrifices needed to be made continually due to their inadequacy (Hebrews 10:11). Christ’s one perfect sacrifice definitively dealt with sin, making it unnecessary for Him to ever repeat His offering. Therefore, believers can have assurance of their salvation based on what Christ has accomplished definitively in His death and resurrection.