How do we know Christ is a successful Savior?

The effectiveness of Christ as our Savior is rooted in His finished work on the cross as detailed in John 19:30, where He proclaimed, 'It is finished.' This statement signifies the complete and perfect sacrifice He made for our sins. Furthermore, Christ did not just redeem us; He ensured that all prophecies, types, and pictures of Him in the Old Testament were perfectly fulfilled in His person and work. The assurance of our salvation aligns with the belief that Christ's shed blood is sufficient to justify, redeem, and sanctify His covenant people.