How do we know Christ's atoning work was determined by God?

The doctrine of God's sovereignty over Christ's atoning work is crucial to Reformed theology. According to Acts 2:23, Jesus was 'delivered up according to the definite plan and foreknowledge of God.' This highlights that Christ's sacrifice was not a mere accident but meticulously orchestrated in God's eternal counsel. It fulfills the types and shadows presented in the Old Testament, such as the Day of Atonement, where God's required means for forgiveness predetermined the need for a perfect sacrifice that would ultimately address sin once and for all.