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 18:1(Pro. 18:1-24)
Through desire . . . seeketh--that is, seeks selfish gratification.
intermeddleth . . . wisdom--or, "rushes on" (Pro 17:14) against all wisdom, or what is valuable (Pro 2:7).
pro 18:2that his heart . . . itself--that is, takes pleasure in revealing his folly (Pro 12:23; Pro 15:2).
pro 18:3So surely are sin and punishment connected (Pro 16:4).
wicked, for "wickedness," answers to
ignominy, or the state of such; and
contempt, the feeling of others to them; and to
reproach, a manifestation of contempt.
pro 18:4Wise speech is like an exhaustless stream of benefit.
pro 18:5accept the person--(Compare Psa 82:2). "It is not good" is to be supplied before "to overthrow."
pro 18:6The quarrelsome bring trouble on themselves. Their rash language ensnares them (Pro 6:2).
pro 18:8(Compare Pro 16:28).
as wounds--not sustained by the Hebrew; better, as "sweet morsels," which men gladly swallow.
innermost . . . belly--the mind, or heart (compare Pro 20:27-30; Psa 22:14).
pro 18:9One by failing to get, the other by wasting wealth, grows poor.
waster--literally, "master of washing," a prodigal.
pro 18:10name of the Lord--manifested perfections (Psa 8:1; Psa 20:2), as faithfulness, power, mercy, &c., on which men rely.
is safe--literally, "set on high, out of danger" (Psa 18:2; Psa 91:4).
pro 18:11contrasts with Pro 18:10 (compare Pro 10:15). Such is a vain trust (compare Psa 73:6).
pro 18:12(Compare Pro 15:33; Pro 16:18).
pro 18:13Hasty speech evinces self-conceit, and ensures shame (Pro 26:12).
pro 18:14infirmity--bodily sickness, or outward evil. The spirit, which sustains, being wounded, no support is left, except, as implied, in God.
pro 18:15(Compare Pro 1:5, Pro 1:15, Pro 1:31).
pro 18:16(Compare Pro 17:8, Pro 17:23). Disapproval of the fact stated is implied.
pro 18:17One-sided statements are not reliable.
searcheth--thoroughly (Pro 17:9, Pro 17:19).
pro 18:18The lot--whose disposal is of God (Pro 16:13), may, properly used, be a right mode of settling disputes.
pro 18:19No feuds so difficult of adjustment as those of relatives; hence great care should be used to avoid them.
pro 18:20(Compare Pro 12:14; Pro 13:2). Men's words are the fruit, or, increase of his lips, and when good, benefit them.
satisfied with--(Compare Pro 1:31; Pro 14:14).
pro 18:21Death and life--or, the greatest evil and good.
that love it--that is, the tongue, or its use for good or evil.
eat . . . fruit--(Compare Pro 18:19; Jam 1:19).
pro 18:22The old versions supply "good" before the "wife," as the last clause and Pro 19:14 imply (compare Pro 31:10).
pro 18:23the rich . . . roughly--He is tolerated because rich, implying that the estimate of men by wealth is wrong.
pro 18:24A man . . . friendly--better, "A man . . . (is) to, or, may triumph (Psa 108:9), or, shout for joy (Psa 5:11), that is, may congratulate himself." Indeed, there is a Friend who is better than a brother; such is the "Friend of sinners" [Mat 11:19; Luk 7:34], who may have been before the writer's mind.