How do we know salvation is God's work and not ours?

The doctrine of salvation emphasizes that it is a divine act initiated and completed by God. Ephesians 2:8-9 clearly states that we are saved by grace through faith, and this not of ourselves; it is the gift of God. Human ability, or the lack thereof, does not impede God's ability to save. Instead, it is His choice and action that lead to salvation. The finished work of Christ on the cross is what secures salvation — 'It is finished' (John 19:30) signifies that Christ completed all that was necessary for redemption. Therefore, any reliance on our works is eliminated, confirming that salvation rests entirely in God’s sovereign grace.