Speech turned from its true purpose, the wandering eye that leads on to evil, action hasty and inconsiderate, are the natural results where we do not "above all keeping keep our heart" Proverbs 4:23.

A froward mouth - Beware of hastiness, anger, and rash speeches.
And perverse lips - Do not delight in nor acquire the habit of contradicting and gainsaying; and beware of calumniating and backbiting your neighbor.

Put away from thee a froward mouth,.... A mouth speaking froward and perverse things; things contrary to right reason, to the law of God, and Gospel of Christ; blasphemies against God or men; every thing that is untrue, unchaste, unjust, foolish, and filthy; all swearing, lying, and everything that is repugnant to truth and justice. Some understand it of men that are liars, blasphemers, and froward persons, who are to be shunned and avoided, and to be debarred the houses and society of good men;
and perverse lips put far from thee; do not make use of them thyself, nor keep company with men of such a character. Much the same thing is meant as before.

a froward mouth--that is, a mouth, or words of ill nature. The Hebrew word differs from that used (Proverbs 2:15; Proverbs 3:32).
perverse--or, "quarreling."
lips--or, "words."

The תּוצאות are the point of a thing, e.g., of a boundary, from which it goes forth, and the linear course proceeding from thence. If thus the author says that the תּוצאות חיּים go out from the heart,
(Note: The correct form here is כּי־ממּנּוּ, with the Makkeph to כי.)
he therewith implies that the life has not only its fountain in the heart, but also that the direction which it takes is determined by the heart. Physically considered, the heart is the receptacle for the blood, in which the soul lives and rules; the pitcher at the blood-fountain which draws it and pours it forth; the chief vessel of the physically self-subsisting blood-life from which it goes forth, and into which it disembogues (Syst. der bib. Psychol. p. 232). What is said of the heart in the lower sense of corporeal vitality, is true in the higher sense of the intellectual soul-life. The Scripture names the heart also as the intellectual soul-centre of man, in its concrete, central unity, its dynamic activity, and its ethical determination on all sides. All the radiations of corporeal and of soul life concentrate there, and again unfold themselves from thence; all that is implied in the Hellenic and Hellenistic words νοῦς, λόγος, συνείδησις, θυμός, lies in the word καρδία; and all whereby בּשׂר (the body) and נפשׁ (the spirit, anima) are affected comes in לב into the light of consciousness (Id. p. 251). The heart is the instrument of the thinking, willing, perceiving life of the spirit; it is the seat of the knowledge of self, of the knowledge of God, of the knowledge of our relation to God, and also of the law of God impressed on our moral nature; it is the workshop of our individual spiritual and ethical form of life brought about by self-activity - the life in its higher and in its lower sense goes out from it, and receives from it the impulse of the direction which it takes; and how earnestly, therefore, must we feel ourselves admonished, how sacredly bound to preserve the heart in purity (Psalm 73:1), so that from this spring of life may go forth not mere seeming life and a caricature of life, but a true life well-pleasing to God! How we have to carry into execution this careful guarding of the heart, is shown in Proverbs 4:24 and the golden rules which follow. Mouth and lips are meant (Proverbs 4:24) as instruments of speech, and not of its utterance, but of the speech going forth from them. עקּשׁוּת, distorsio, refers to the mouth (Proverbs 6:12), when what it speaks is disfiguring and deforming, thus falsehood as the contrast of truth and love (Proverbs 2:12); and to the lips לזוּת, when that which they speak turns aside from the true and the right to side-ways and by-ways. Since the Kametz of such abstracta, as well of verbs 'ו'ע like לזוּת, Ezekiel 32:5, as of verbs 'ה'ל like גּלוּת, Isaiah 45:13, חזוּת, Isaiah 28:18, is elsewhere treated as unalterable, there lies in this לזוּת either an inconsistency of punctuation, or it is presupposed that the form לזוּת was vocalized like שׁבוּת = שׁבית, Numbers 21:29.

Mouth - All sorts of sinful words.