How do we know salvation is finished?

Salvation is understood to be finished both in the mind of God from eternity and as a historical reality accomplished at the cross. This is central to Reformed theology, particularly as noted in the declaration of Christ, 'It is finished' (John 19:30). This statement signifies the completion of the sacrificial system and the fulfillment of God's redemptive plan through Christ's sacrifice—no further work is needed for atonement. Believers find assurance in this completed work, enjoying peace with God and knowing that their salvation is secure in Christ's finished work.