A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
pro 20:1(Pro. 20:1-30)
mocker--scorner. Such men are made by wine.
strong drink--made by spicing wine (compare Isa 5:11, Isa 5:22); and it may include wine.
raging--or boisterous as a drunkard.
deceived--literally, "erring," or reeling.
pro 20:2(Compare Pro 19:12). Men who resist authority injure themselves (Rom 13:2).
pro 20:3to cease from strife--or, better, "to dwell from or without strife," denoting the habit of life.
fool . . . meddling-- (Pro 17:14).
pro 20:4shall . . . beg--literally, "ask" (in this sense, Psa 109:10).
pro 20:5Counsel . . . water--that is, deeply hidden (Pro 18:4; Psa 13:2). The wise can discern well.
pro 20:6Boasters are unreliable.
goodness--or, "kind disposition."
pro 20:7The conduct of good men proclaims their sound principles. God's covenant and their good example secure blessing to their children (Pro 4:26; Psa 112:1-2).
pro 20:8As in Pro 14:35; Pro 16:10, Pro 16:15, this is the character of a good king, not of all kings.
pro 20:9The interrogation in the affirmative strengthens the implied negation (compare Job 15:14; Ecc 7:20).
pro 20:10Various measures, implying that some are wrong (compare Pro 11:1; Pro 16:11).
pro 20:11The conduct of children even is the best test of principle (compare Mat 7:16).
pro 20:12Hence, of course, God will know all you do (Psa 94:9).
pro 20:13Activity and diligence contrasted with sloth (Pro 6:9; Pro 10:11).
lest . . . poverty--literally, "be deprived of inheritance."
pro 20:14when . . . his way--implying that he goes about boasting of his bargains.
pro 20:15The contrast denotes the greater value of knowledge (compare Pro 3:14-16).
pro 20:16Take his garment--implies severe exaction, justified by the surety's rashness.
a strange woman--by some readings "strangers," but the former here, and in Pro 27:13, is allowable, and strengthens the sense. The debauchee is less reliable than the merely careless.
pro 20:17Bread . . . sweet--either as unlawfully (Pro 9:17) or easily obtained.
mouth . . . gravel--well expresses the pain and grief given at last.
pro 20:18(Compare Pro 15:22). Be careful and considerate in important plans.
pro 20:19Those who love to tell news will hardly keep secrets.
flattereth . . . lips--(compare Margin; Pro 1:10).
meddle . . . him--literally, "join," or "associate with."
pro 20:20his lamp--(Compare Pro 13:9; Pro 24:20).
pro 20:21gotten hastily--contrary to God's providence (Pro 28:20), implying its unjust or easy attainment; hence the man is punished, or spends freely what he got easily (compare Pro 20:17).
pro 20:22(Compare Psa 27:14; Rom 12:17-19).
pro 20:23(Compare Pro 20:10; Pro 11:1).
pro 20:24Man's goings--literally, "Stately steppings of a strong man."
a man--any common man.
pro 20:25devoureth . . . holy--or, better, "who rashly speaks promises," or "devotes what is holy," consecrating any thing. This suits better the last clause, which expresses a similar view of the results of rashly vowing.
pro 20:26(Compare Pro 20:8).
bringeth . . . over them--The wheel was used for threshing grain. The figure denotes severity (compare Amo 1:3).
pro 20:27The spirit . . . Lord--Men's minds are God's gifts, and thus able to search one another (compare Pro 20:5; Pro 18:8, Pro 18:17; Co1 2:11).
pro 20:28(Compare Pro 3:3; Pro 16:6, Pro 16:12).
pro 20:29The glory of young men . . . the beauty of old men--Each age has its peculiar excellence (Pro 16:31).
pro 20:30blueness--literally, "joining," the process of uniting the edges of a wound throws off purulent matter.
stripes . . . belly--So punishment provides healing of soul (Pro 18:8), by deterring from evil courses.