How do we know that Christ's work is sufficient for our acceptance?

Scripture emphasizes that Christ's sacrificial act was complete and perfect, fulfilling the law on our behalf. In Colossians 2:13-14, we find that our trespasses and the legal demands against us were nailed to the cross. This suggests that nothing else is necessary to appease God's justice. The notion that human effort could supplement Christ's work undermines the sufficiency of His sacrifice, according to Hebrews 10:14, which tells us that He has perfected for all time those who are being sanctified. Therefore, confidence in His work alone reassures us of our acceptance.