John Gill Commentary Ezra 7:25

"And thou, Ezra, after the wisdom of thy God that is in thy hand, appoint magistrates and judges, who may judge all the people that are beyond the River, all such as know the laws of thy God; and teach ye him that knoweth them not." — Ezra 7:25 (ASV)

And you, Ezra, after the wisdom of your God, that is in your
hand
Which he had a large share of from the Lord, and could readily make use of to good purpose; and this may be meant of the law of God made with the highest wisdom, and to know and observe which is an instance of wisdom in men, (Deuteronomy 4:6) ,

set magistrates and judges, which may judge all the people that are
beyond the river, all such as know the laws of your God ;
such as God, in his great wisdom, directed to in his wise law to be appointed over the people, to judge righteous judgment; to inform them in all matters of controversy that might arise among them, and decide them according to it; and lead them into a greater and better knowledge of it, (Deuteronomy 16:18) (17:9) . Jarchi takes the word for "set" to be a comparative, and the sense to be, that the wisdom of Ezra was greater than the judges that judged the people, than them that knew the law:

and teach you them that know them not ;
such people that were ignorant thereof; though the above writer interprets this of ignorant judges, "the judge that knows not to judge, make him know judgment to do it."