The story
From antinomian + -ism, coined by Martin Luther, notably used in his Against the Antinomians (1539).
Etymology from Wiktionary, CC BY-SA 4.0.
antinomianism
an·ti·no·mi·an·ismToday it means: The belief or teaching that because only the spiritual "law of faith" (Romans 3:27) is essential for salvation, obedience to any practical or moral law has no role to play, even as a guide to conduct or as a test of the genuineness of faith. Full definition →