Do you believe in the forgiveness of sins? On what basis? I heard a famous person say he hoped God would tell him upon his death that he had done enough to get to heaven.
The writer of Hebrews reminds us of the firm foundation for our faith and forgiveness: Jesus paid it all, once and for all.
Jesus' perfect sacrifice suffices for all who will believe in him. His crucifixion never needs to be repeated. Jesus suffered one and for all so that we could be forgiven once and for all.
How then shall we live? First, we receive his forgiveness. Second, we serve him out of gratitude. Nothing in our hands we bring; simply to his cross we cling.