Final answer:
The theory that states a ruler's power stems directly from the will of God is called the divine right of kings.
Step-by-step explanation:
The theory that states a ruler's power stems directly from the will of God is called the divine right of kings. According to this theory, monarchs are believed to be chosen by God and have a divine mandate to rule. This concept was widely embraced during the medieval and early modern periods and justified the absolute power of monarchs.
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