John Gill Commentary Ecclesiastes 7:19

"Wisdom is a strength to the wise man more than ten rulers that are in a city." — Ecclesiastes 7:19 (ASV)

Wisdom strengthens the wise
Against such extremes as before mentioned; it is a guard about him, as well as a guide to him; it is a defence to him, as before observed, (Ecclesiastes 7:12) ; and is better than strength of body, or weapons of war, (Ecclesiastes 9:16Ecclesiastes 9:18) ; and a wise man does greater things by it than a strong man with them, and is safer with it than he can be by them.

Some understand this of Christ, the Wisdom of God, without whom a good man can do nothing, but all things through him strengthening him; and who being a strong tower and place of refuge to him, he is safer in him than if he was in the strongest garrison, and under the protection of ever so large a number of valiant men: Christ, and grace from him, strengthen more than ten mighty [men] which are in the city ;
that is, than many mighty men, or men of war, which guard a city; the city of Jerusalem, or any other.

The Targum applies this to Joseph, and paraphrases it, ``the wisdom of Joseph the son of Jacob helped him to make him wiser than all his ten righteous brethren.''