Ingratitude
Ingratitude — the failure to acknowledge or return thanks for benefits received — is treated in Scripture as a significant moral failure that reflects spiritual blindness. The OT records Israel's persistent ingratitude toward God despite his mighty acts: forgetting the Exodus, complaining against divine provision in the wilderness (Num. 11:4–6; Ps. 78:10–17), and abandoning him for Baal. The prophets condemn this as the essence of Israel's sin: "Sons have I reared and brought up, but they have rebelled against me" (Isa. 1:2). In the Gospels, the cleansing of the ten lepers and the return of only one to give thanks illustrates human ingratitude starkly (Luke 17:17–18). Paul identifies ingratitude as one of the marks of end-time moral collapse: "ungrateful, unholy" (2 Tim. 3:2). More fundamentally, Romans 1:21 traces the origin of human idolatry and moral decline to this root: humanity "did not honor him as God or give thanks to him." Gratitude, by contrast, is integral to the Christian life: "Give thanks in all circumstances" (1 Thess. 5:18; cf. Phil. 4:6; Col. 3:17).