How do we know salvation is a work of the heart?

As taught in the sermon, salvation is not merely an intellectual assent or participation in rituals like baptism; it is fundamentally a work of the heart. Acts 8:21 shows Peter's warning to Simon that his heart was not right with God, indicating that true faith requires a supernatural change wrought by the Holy Spirit. Ezekiel 36:26 speaks to this transformation, where God promises, 'A new heart also will I give you, and a new spirit will I put within you.' This emphasizes that a true conversion to Christ arises from a heart that is awakened to His holiness and grace, producing repentance and faith in Him alone.