How do we know that redemption through Christ is eternal?

Hebrews 10:14 emphasizes that by one offering, Christ has perfected forever those who are sanctified. This reiterates the idea that His sacrifice was once and for all, eliminating the need for repeated offerings that were insufficient in the past. The concept of eternal redemption hinges on the sufficiency and finality of Christ’s work; no other sacrifice is needed. In contrast to the repetitive nature of Old Testament sacrifices, which served merely as a foreshadowing of Christ's ultimate sacrifice, the redemption secured by Jesus is everlasting and unchangeable. It underscores the security that all believers have in His finished work.