What does the Bible say about Christ's accomplishments at Calvary?

In Hebrews 10:9-14, the writer emphasizes that Jesus Christ came to do the will of God, which included taking away the first covenant of sacrifices to establish a new covenant of grace. His death is not just a historical event, but a decisive accomplishment that sanctifies and perfects those He died for. Hebrews 10:14 states, 'For by one offering, He hath perfected forever them that are sanctified,' illustrating that His sacrifice was both sufficient and effectual, securing salvation for His people once and for all.