'Obey' in the Bible

If you fear the LORD, serve him, obey him, and don't rebel against the commandment of the LORD, then both you and the king who rules over you will truly follow the LORD your God.

But if you don't obey the LORD and rebel against the commandment of the LORD, then the LORD will turn against you as he did against your ancestors.

but now your kingdom won't be established. The LORD has sought for himself a man after his own heart, and the LORD has appointed him as Commander-in-Chief over his people because you didn't obey that which the LORD commanded you."

Why didn't you obey the LORD, but grabbed the spoil and did evil in the LORD's sight?"

Saul told Samuel, "I did obey the LORD. I went on the mission on which the LORD sent me, I brought Agag king of Amalek, and I completely destroyed the Amalekites.

Samuel said, "Does the LORD delight as much in burnt offerings and sacrifices as in obeying the LORD? Surely, to obey is better than sacrifice, to pay attention is better than the fat of rams.

Because you didn't obey the LORD and didn't display his fierce anger against Amalek, therefore, the LORD will do this thing to you today.