Why is Christ's atonement necessary for our salvation?

The atonement of Christ is central to the Christian faith because it addresses the holiness of God, which cannot overlook sin. Since God is utterly separate from unrighteousness, the sacrificial death of Christ serves as the only means of satisfying the righteous indignation due to our sin. By being both the Lion of Judah and the sacrificial Lamb, Jesus took upon Himself the punishment for our sins, thereby clearing the way for us to be reconciled to a holy God. This atonement ensures that believers are seen as righteous in God's eyes, not because of their own merit but through the completed work of Christ.