The throne represents the authority of the king. Alternate translation: "became king, as his father David had been" (See: [[rc://en/ta/man/translate/figs-metonymy]])
This can be translated in active form. Alternate translation: "Yahweh firmly established Solomon's rule" or "Yahweh caused Solomon to take complete control of the kingdom" (See: [[rc://en/ta/man/translate/figs-activepassive]])