How do we know that Jesus' sacrifice was complete and sufficient?

The phrase 'It is finished' encapsulates the essence of Christ's atoning work on the cross, signaling the completion of the divine plan of salvation. As stated in John 19:30, Jesus's cry isn't merely a resignation to death but a vibrant declaration of victory. By fulfilling prophecies and absorbing the wrath of God for sin, He provided a way for humanity to be reconciled to God. The tearing of the temple veil as described in Matthew 27:51 signifies that access to God has been restored for all who believe, underscoring that Christ's sacrifice was not only complete but sufficient for the salvation of His elect.