How do we know that salvation is the work of the Father, Son, and Holy Spirit?

In the doctrine of salvation, it is vital to recognize the roles of the Father, Son, and Holy Spirit. The Father elects, the Son redeems, and the Holy Spirit regenerates the believer. All three are active and equal in the process of salvation, shown clearly in biblical parables, such as in Luke 15, where the seeking and finding of lost individuals is attributed to the divine initiative of God. This cooperative work of the Trinity in salvation is foundational to understanding the Reformed view of grace and the assurance of salvation, reinforcing the belief that God's intent and power accomplish the salvation of His chosen ones.