Why is it significant that Christ is called the 'Surety' of a better testament?

The term 'Surety' signifies one who guarantees the fulfillment of a promise or obligation, and when applied to Christ as in Hebrews 7:22, it emphasizes His role in the new covenant. Unlike the old covenant, which was temporary and required repeated sacrifices, Christ's suretyship secures an eternal redemption through His one sacrifice, assuring believers of their standing and relationship with God. This notion underscores the finality and supremacy of Christ’s work as He fulfills all that is required for salvation, ensuring that those chosen will not be lost.