The great hindrance to all true wisdom is the thought that we have already attained it.

Be not wise in thine own eyes,.... So as to act independently of God; not to trust in him, nor acknowledge him, nor seek to him for help and direction; nor ask nor take the advice of others; but, being conceited and self-sufficient, lean to thine own understanding, as being wise enough to conduct all affairs in life by thy own discretion; and in matters of religion wiser than thy teachers, and even than the Scriptures, being wise above that which is written; pleasing thyself with thine own wisdom, as exceeding others; glorying in it as thine own acquisition, and not ascribing it to God, so far as it any ways deserves the name of wisdom; though for the most part that which men glory in, and are conceited of, is not wisdom, but folly; and at least it is their folly to boast of it and be elated with it; see Isaiah 5:21, Romans 12:16;
fear the Lord; which is true wisdom; and, where this is not, there is none, let men be ever so conceited; and where this is there is humility; these two go together, and make a man wise, rich, and honourable, Proverbs 22:4. The fear of the Lord is opposed to pride, high-mindedness, and vain conceit, Romans 11:20; this includes reverence of God, faith in him, dependence on him, acknowledgment of him, seeking to him for direction, and carefulness not to offend him;
and depart from evil; from the evil of self-confidence and self-conceit, and from all other evil; the fear of God influences men to avoid sin, and abstain from all appearance of it; by means and through the exercise of it men forsake it, and keep at a distance from it, Proverbs 16:6. Nehemiah could not do as others did, because of the fear of the Lord; and Job was a man that feared God, and therefore he avoided that which was evil, Nehemiah 5:15.

There is not a greater enemy to the fear of the Lord in the heart, than self-conceit of our own wisdom. The prudence and sobriety which religion teaches, tend not only to the health of the soul, but to the health of the body. Worldly wealth is but poor substance, yet, such as it is, we must honour God with it; and those that do good with what they have, shall have more to do more good with. Should the Lord visit us with trials and sickness, let us not forget that the exhortation speaks to us as to children, for our good. We must not faint under an affliction, be it ever so heavy and long, not be driven to despair, or use wrong means for relief. The father corrects the son whom he loves, because he loves him, and desires that he may be wise and good. Afflictions are so far from doing God's children any hurt, that, by the grace of God, they promote their holiness.

(Compare Proverbs 27:2; Romans 12:16).
fear . . . evil--reverentially regarding His law.