How do we know that the death of Jesus atones for sin?

The atonement provided by Jesus through His death is established in Scripture as the fulfillment of God's covenant promise. In John 19:31-37, John emphasizes that the events surrounding Jesus' crucifixion were to fulfill the Scriptures, which detail that the Messiah would suffer for the sins of the people. Jesus' precisely timed death coincides with the sacrificial lamb's death in the Jewish tradition, representing the final and perfect sacrifice that could remove sin completely, as affirmed in Hebrews 10:12.