How do we know that Christ's sacrifice redeemed us?

The doctrinal assurance of Christ's redemptive work comes from both the Old and New Testaments. In Revelation 5:9, we see that Christ has redeemed us to God by His blood, signifying a complete and effective atonement. This is further supported by Psalm 96, which calls for declaring God's wonders and His salvation, emphasizing His sovereign choice and ability to save. Christ's statement in John 10:15, where He claims to lay down His life for the sheep, solidifies the understanding that His sacrificial death was not a mere attempt at redemption but a definitive act that guarantees the salvation of His chosen people.