Psalms 122:5

5.For there were set thrones for judgment. He means, that the throne of the kingdom was fixed or established at Jerusalem, or that there it had its permanent seat. Among that people some order of judgments had always existed; these, however, had formerly been in an unsettled state, and frequently changed, but God at length ordained, in the person of David, a new government which should flow in a continual course; for it was his will that the children of David should succeed their father in this royal dignity from age to age until the coming of Christ. The Prophet has a little before spoken of the Temple and the priesthood; and now he affirms, that this kingdom, which God had erected, will be firm and stable; in order to distinguish it from all the other kingdoms of the world, which are not only temporary, but also frail and subject to a variety of changes. This everlastingness of the kingdom has been expressly confirmed by other Prophets in various parts of their’ writings, and not without cause; for the object was, to teach the faithful that God would be the guardian of their welfare only upon the supposition of their remaining under the protection and defense of David, and that, therefore, if they desired to continue in safety and to prosper, they should not make for themselves new kings at their own pleasure, but should live quietly under that kind of government which God had set up among them. The repetition of the word throne is emphatic. There, says the Psalmist, the throne of judgment and equity is erected. Then he adds, the throne of the house of David; for it was the will of God that the right and prerogative of reigning should continue in David’s posterity, until the true everlastingness of this kingdom should be manifested in the person of Christ.