We know grace is sufficient for salvation because Scripture affirms that salvation is granted solely by God's grace, not by our works.
The sufficiency of grace in salvation is foundational to the Reformed understanding of the doctrine. Ephesians 2:8-9 clearly states that we are saved by grace through faith, not of ourselves; it is the gift of God. This emphasizes that no human efforts or merits earn salvation, making it entirely a work of divine grace. The doctrine of total depravity further illustrates that we, in our natural state, are unable to contribute to our salvation. Thus, the assurance lies in God's unmerited favor pouring out upon the humble, without which we could do nothing to save ourselves.
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