The "evil" of Ecclesiastes 10:5 is here specified as that caprice of a king by which an unworthy favorite of low origin is promoted to successive dignities, while a noble person is degraded or neglected.

Folly is set in great dignity, and the (e) rich sit in low place.
(e) They who are rich in wisdom and virtue.

Folly is set in great dignity,.... Or "in great heights" (q); in high places of honour and truest; even foolish and wicked men; men of poor extraction, of low life, and of mean abilities and capacities; and, which is worse, men vile and vicious, as Doeg the Edomite, Haman the Amalekite, and others;
and the rich sit in low places; men not only of fortune and estates, and above doing mean and little actions, and so more fit for such high places; but men rich in wisdom and knowledge, of large capacities and of great endowments of mind, and so abundantly qualified for posts in the administration of government; and, above all, men rich in grace, fearing God, and hating coveteousness, as rulers ought to be, Exodus 18:21; and yet these sometimes are neglected, live in obscurity, who might otherwise be very useful in public life. The Targum interprets this and the following verse of the Israelites in exile and poverty among the Gentiles for their sins; so Jarchi.
(q) , Sept. "in celsitudinibus amplis", Piscator, Amama, Gejerus; "in sublimitatibus amplis", Cocceius; "in altitudinibus magnis", Rambachius; "in great height", Broughton.

rich--not in mere wealth, but in wisdom, as the antithesis to "folly" (for "foolish men") shows. So Hebrew, rich, equivalent to "liberal," in a good sense (Isaiah 32:5). Mordecai and Haman (Esther 3:1-2; Esther 6:6-11).

"Folly is set on great heights, and the rich must sit in lowliness. I have seen servants upon horses, and princes like servants walking on foot." The word הסּכל (with double seghol, Aram. סכלוּ) is used here instead of those in whom it is personified. Elsewhere a multiplicity of things great, such as עמּים, מים, and the like, is heightened by רבּים (cf. e.g., Psalm 18:17); here "great heights" are such as are of a high, or the highest degree; rabbim, instead of harabbim, is more appos. than adject. (cf. Genesis 43:14; Psalm 68:28; Psalm 143:10; Jeremiah 2:21), in the sense of "many" (e.g., Ginsburg: "in many high positions") it mixes with the poetry of the description dull prose.
(Note: Luzz. reads נתן: "Folly brings many into high places." The order of the words, however, does not favour this.)
'Ashirim also is peculiarly used: divites = nobiles (cf. שׁוע, Isaiah 32:5), those to whom their family inheritance gives a claim to a high station, who possess the means of training themselves for high offices, which they regard as places of honour, not as sources of gain. Regibus multis, Grotius here remarks, quoting from Sallust and Tacitus, suspecti qui excellunt sive sapientia sive nobilitate aut opibus. Hence it appears that the relation of slaves and princes to each other is suggested; hoc discrimen, says Justin, 41:3, of the Parthians, inter servos liberosque est quod servi pedibus, liberi nonnisi equis incedunt; this distinction is set aside, princes must walk 'al-haarěts, i.e., beregel (beraglēhěm), and in their stead (Jeremiah 17:25) slaves sit high on horseback, and rule over them (the princes), - an offensive spectacle, Proverbs 19:10. The eunuch Bagoas, long all-powerful at the Persian Court, is an example of the evil consequences of this reversal of the natural relations of men.

The rich - Wise and worthy men, rich in endowments of mind.