1 Samuel 15: 1-23
King Saul, like many Christians today, thought God would be pleased with just partial obedience to His commands. It cost him his kingship.
Make a joyful noise unto the LORD, all ye lands. Serve the LORD with gladness: come before his presence with singing. Know ye that the LORD he is God: it is he that hath made us, and not we ourselves; we are his people, and the sheep of his pasture. ~ Psalm 100:1-3