When you were a child and misbehaved, your parents would hit you to force you to obey. At this time, power is violence.

When you grew a little older and misbehaved, your parents would cut off your allowance to force you to obey. At this time, power is resource monopoly.

Once you become financially independent and misbehave, your parents would use filial piety, societal judgment, and other forms of moral coercion. At this time, power is ideology and public opinion.

In summary, power is making others do what you want them to do, even if it goes against their own will, and the more effective methods are: military deterrence (king), resource monopoly (merchant), and ideology (clergy).