This sermon examines how gratitude is foundational to Christian living and how it actively shapes our hearts. Using the account of the ten lepers in Luke 17, we see that genuine thankfulness is rare—even among those richly blessed by God. Scripture teaches that gratitude is not a polite social gesture but God’s will for His people (1 Thess. 5:18). We learn that thankfulness requires an outward focus, reminding us that life is not about ourselves and guarding us against forgetfulness and entitlement, as Moses warned in Deuteronomy 8. Gratitude also diminishes destructive attitudes such as worry, discontentment, discouragement, and spiritual distance from God, redirecting our hearts toward trust and joy. As it grows in us, gratitude bears godly fruit: it honors God and others, makes us more like Christ—who Himself modeled thankfulness—and transforms our words, relationships, and influence into refreshing, life-giving blessings. Ultimately, a grateful heart keeps us grounded in the goodness of God and aligned with the new life we have through Christ.