And all who dwell on the earth will worship the beast—all whose names have not been written from the foundation of the world in the Book of Life belonging to the Lamb who was slain. — Revelation 13:8

Before the foundation of the world, the Lamb was slain. The cross wasn't Plan B—it was the eternal purpose of God, settled before Adam drew breath. Christ, our Passover Lamb, was sacrificed for us, delivered up by the determinate counsel of God. This grace was given us in Christ before the ages began.