How do we know the atonement of Christ is sufficient for our sins?

The sufficiency of Christ's atonement relies on His complete and sacrificial act on the cross, where He bore the sins of His people. In Mark 14:34, He refers to the cup of suffering, which signifies the weight of sin He would carry. Jesus drank this cup to the very last drop, demonstrating that no further payment for sin is needed. The depth of His suffering at Gethsemane, where He was 'sore amazed,' suggests the gravity of sin's implications and His willingness to endure it all for our sakes. Because He is both fully God and fully man, His sacrifice was perfect and able to atone for every sin, ensuring that those He died for are fully redeemed.