How do we know Jesus Christ's sacrifice was sufficient?

The sufficiency of Christ's sacrifice is found in His perfection and voluntary nature. Hebrews 9:14 indicates that Christ offered Himself without spot before God, fulfilling the requirement of being without blemish as stated in Leviticus. His sacrifice was not only complete but also willingly given, as demonstrated in John 10:17-18 where Jesus asserts that He lays down His life voluntarily. This confirms that His sacrifice fully satisfies God's justice, making Him the perfect atoning sacrifice for our sins.