How do we know salvation is only by grace?

Salvation by grace is a core teaching of Scripture, as articulated in Ephesians 2:8-9, which emphasizes that it is by grace through faith that believers are saved, and not by works. This doctrine of grace underscores that human efforts cannot earn salvation; instead, it is entirely the work of God. The Reformed perspective highlights that God's grace is irresistible and unconditional, meaning those whom He has chosen are saved solely because of His sovereign will and love, reflecting His glory rather than any merit of their own.