How do we know salvation is purely by grace?

The sermon emphasizes that salvation is entirely of the Lord and not contingent on human works. Paul highlights in Ephesians that God’s choice of individuals for salvation is rooted in His electing love and grace. Humans, due to their natural depravity, cannot achieve understanding or salvation on their own. This truth is foundational in Reformed theology, affirming that salvation is a gift bestowed upon us solely by God's mercy and grace, thus eliminating any grounds for human boasting.