Psalms 9:4

For thou hast maintained my right and my cause
Or vindicated and established his righteous cause; God had pleaded and defended it, and by the flight, fall, and ruin of his enemies, had clearly made it appear that his cause was just and good;

thou sittest in the throne judging right;
God has not only a throne of grace on which he sits, and from whence he distributes grace and mercy to his people, but he has a throne of judgment, and which is prepared for it, as in ( Psalms 9:7 ) ; where he sits as the Judge of all the earth, and will do right; nor can he do otherwise, though his judgments are not always manifest in the present state of things; and the vindication of the psalmist's innocence and uprightness is another reason of his joy and gladness.