金光明最勝王經疏 5.36

5.36

As for explaining the title: Being sovereign, luminous, and possessing spiritual functions is called "heavenly" (deva). Being the refuge of the multitude of devas, ruling and commanding them as their lord, is called "king" (rāja). Because they are kings of heaven, it is explained as a determinative compound (tatpuruṣa). Their directions and citadels differ, their governing is divided into four, and they additionally carry a numerical name. "Protecting" refers to defense and sustenance: defense eliminates calamities for them, and sustenance increases their merit and wisdom. The four heavenly [kings] are the protectors, and the "country" is what is protected; the agent and the object are named together. Because it extensively elucidates this, it is called the "Chapter on the Four Heavenly Kings Protecting the Country."