The deep interdependence of morality and intellect. We have a right judgment in all things in proportion as our hearts seek to know God. Compare James 1:23-24.

They that seek the Lord understand all things - They are wise unto salvation; they "have the unction from the Holy One, and they know all things," 1-John 2:20, every thing that is essentially needful for them to know, in reference to both worlds.

Evil men understand not judgment,.... Or, "men of wickedness" (b); that are under the governing power of it; who are given up and give up themselves unto it; who, like Ahab, sell themselves to work wickedness: these know not what is just and right between man and man, at least not to do it; they know it not practically; they are wise to do evil, but to do good have no knowledge, Jeremiah 4:22; they know not the law of God, the rule of judgment, justice, and equity; at least not the extensiveness and spirituality of it, Jeremiah 8:7; and much less the Gospel of Christ, which is sometimes so called, Isaiah 42:1. Nor do they notice, as they should, to the judgments of God in the earth; they do not consider his work, and the operation of his hand; the vengeance he takes on wicked men, so Jarchi interprets it; nor do they take any notice of the judgment to come, at which they must appear, and into which they will be brought, and all things done by them;
but they that seek the Lord understand all things; this character describes all good men that seek the Lord, in private and in public, that seek him by prayer and supplication, that wait upon him in the ordinances of his house; and all sensible sinners, who seek to Christ for righteousness, for rest, for life and salvation, for more grace from him, for more communion with him, for a greater degree of knowledge of him, and for immortality and eternal life, his kingdom and glory. And such "understand all things"; not in the most full and absolute sense; for this is proper and peculiar to God: nor all things natural and civil, which truly righteous persons, generally speaking, have the least share of, as arts, sciences, languages, trade and commerce in all its branches; and indeed universal knowledge of these things does not belong to anyone alan: nor all things in a religious sense; not all the difficult passages of Scripture, in which there are many things hard to be understood; but all things necessary to salvation; all things relating to their fallen, depraved, and miserable state and condition by nature, and to the way and means of their recovery and salvation by Christ; all things relating to a spiritual and saving knowledge of God in Christ; and to the knowledge of the person, offices, and grace of Christ; and to the work of the Spirit of God upon the heart; and of the doctrines of the Gospel, according to the measure of the gift of Christ, and so as to be food for their souls: and which understanding is given them, and they attain unto and increase in, by seeking the Lord, and using the means of knowledge, the word and ordinances; see 1-Corinthians 2:15. The Targum and Syriac version render it,
"that understand all good things;''
and so Aben Ezra interprets it: the Arabic version is, "they understand it in all things"; that is, judgment, justice, and equity, in all its branches, and practise it.
(b) "viri mali, (in genitivo casu)", Mercerus; "vel malitiae", Baynus, Gejerus.

If a man seeks the Lord, it is a good sign that he understands much, and it is a good means of understanding more.

(Compare John 7:17). Ignorance of moral truth is due to unwillingness to know it.

A similar antithetic distich:
Wicked men understand not what is right;
But they who seek Jahve understand all.
Regarding the gen. expression אנשׁי־רע, vid., under Proverbs 2:14. He who makes wickedness his element, falls into the confusion of the moral conception; but he whose end is the one living God, gains from that, in every situation of life, even amid the greatest difficulties, the knowledge of that which is morally right. Similarly the Apostle John (1-John 2:20): "ye have an unction from the Holy One, and ye know all things" (οἴδατε πάντα): i.e., ye need to seek that knowledge which ye require, and which ye long after, not without yourselves, but in the new divine foundation of your personal life; from thence all that ye need for the growth of your spiritual life, and for the turning away from you of hostile influences, will come into your consciences. It is a potential knowledge, all-comprehensive in its character, and obviously a human relative knowledge, that is here meant.

Judgment - What is just and right. All things - Which are necessary to be known by them.