Both low and high - Those alike of humble and those of exalted rank, for it pertains equally to all. On the meaning of the "terms" employed here, see the notes at Isaiah 2:9. These truths pertained to the "low;" that is, to those of humble rank, as teaching them not to envy the rich, and not to fear their power; and they pertained to those of exalted rank, as teaching them not to trust in their riches, and not to suppose that they could permanently possess and enjoy them.
Rich and poor together - As equally interested in these truths; that is, What the psalmist was about to say was adapted to impart useful lessons to both classes. Both needed instruction on the subject; and the same class of truths was adapted to furnish that instruction. The class of truths referred to was derived from the powerlessness of wealth in regard to the things of most importance to man, and from the fact that all which a man can gain must soon be left: teaching those of one class that they should not set their heart on wealth, and should not pride themselves on possessing it, and teaching the other class that they should not envy or fear the possessor of riches.

Both low and high,.... Or "both the sons of Adam and the sons of men". By the sons of "Adam" are meant the multitude of the people, as Ben Melech explains it; the common people, the meaner sort, the base things of this world; and such are they, generally speaking, who are called by grace under the Gospel dispensation: and by "the sons of men" are meant the princes, nobles, and great men of the earth; men of high birth and illustrious extraction: so Adam is rendered, "the mean man", and "Ish", the word here used, "the great man", in Isaiah 2:9. And though not many, yet some of this sort are called by grace; and all of them have a peculiar concern in many things spoken of in this psalm; see Psalm 49:12;
rich and poor together: these are called upon to hearken to what is after said, that the one may not be elated with and trust in their riches, and that the other may not be dejected on account of their poverty; and seeing both must die, and meet together at the judgment day; and inasmuch as the Gospel is preached to one as to another; and for the most part the poor hear it, receive it, and are called by it.