| Matthew Henry's Concise Commentary 30:10 Slander not a servant to his master, accuse him not in small matters, to make mischief. 11-14. In every age there are monsters of ingratitude who ill-treat their parents. Many persuade themselves they are holy persons, whose hearts are full of sin, and who practise secret wickedness. There are others whose lofty pride is manifest. There have also been cruel monsters in every age. 15-17. Cruelty and covetousness are two daughters of the horseleech, that still cry, Give, give, and they are continually uneasy to themselves. Four things never are satisfied, to which these devourers are compared. Those are never rich that are always coveting. And many who have come to a bad end, have owned that their wicked courses began by despising their parents' authority. 18-20. Four things cannot be fully known. The kingdom of nature is full of marvels. The fourth is a mystery of iniquity; the cursed arts by which a vile seducer gains the affections of a female; and the arts which a vile woman uses to conceal her wickedness. 21-23 Four sorts of persons are very troublesome. Men of low origin and base spirit, who, getting authority, become tyrants. Foolish and violent men indulging in excesses. A woman of a contentious spirit and vicious habits. A servant who has obtained undue influence. Let those whom Providence has advanced from low beginnings, carefully watch against that sin which most easily besets them.
Pulpit CommentaryVerses 18-20. - A proverb concerning four inscrutable things, connected with the last by mention of the eagle. Verse 18. - There be three things which are too wonderful for me, yea, four which I know not. The great point is the fourth, to which the three previous things lead up, all of them being alike in this, that they leave no trace. The facts are marvellous; Agur feels like Job, "I have uttered that which I understood not, things too wonderful for me, which I knew not" (Job 42:3).
Gill's Exposition of the Entire BibleThere be three things which are too wonderful for me,.... Which were above his reach and comprehension; what he could not find out, nor account for, nor sufficiently admire; yea, four things which I know not; the way of them; as follows.
Jamieson-Fausset-Brown Bible Commentary18-20. Hypocrisy is illustrated by four examples of the concealment of all methods or traces of action, and a pertinent example of double dealing in actual vice is added, that is, the adulterous woman.
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