1 Samuel 15

But Samuel said: "Does the LORD so delight in holocausts and sacrifices as in obedience to the command of the LORD? Obedience is better than sacrifice, and submission than the fat of rams.

For a sin like divination is rebellion, and presumption is the crime of idolatry. Because you have rejected the command of the LORD, he, too, has rejected you as ruler."

1 Samuel 15:22-23