A Divine Work
How was the atonement of Christ applied to believers? It is because of substitution that justification occurs by faith. Since saving faith and justification are blood bought accomplishments of the cross to take care of unbelief and unrighteousness (by imputation, not infusion); the “application” of this substitutionary work occurs at conversion. In eternity it was planned, at Calvary it was accomplished, and at conversion it was applied.