The evil-doers here include not robbers and murderers only Proverbs 1:10-16, but all who leave the straight path and the open day for crooked ways, perverse counsels, deeds of darkness. "To delight etc." Proverbs 2:14 is the lowest depth of all.

The man that speaketh froward things - תהפכות tahpuchoth, things of subverston; from תפך taphach, to turn or change the course of a thing. Men who wish to subvert the state of things, whether civil or religious; who are seditious themselves, and wish to make others so. These speak much of liberty and oppression, deal greatly in broad assertions, and endeavor especially to corrupt the minds of youth.

To deliver thee from the way of the evil man,.... Who is so by nature and practice, who is hardened in sin and abandoned to it, whose course of life is evil, and who endeavours to draw others into the same evil practices; now the Gospel, and a spiritual knowledge of it, are a means of preserving men from following the examples of such persons, and from walking with them in the ways of sin: or from "the evil way" (t), from every evil way, from a vicious course of life; not from idolatry only, as some interpret it, though this may be included, and chiefly designed; but from all manner of sin, from everything that is contrary to the law of God and sound doctrine;
from the man that speaketh froward things; perverse things, things contrary to the light of nature, to divine revelation, to the word of God, both law and Gospel; if a single man is meant, he might be thought to be the man of sin, antichrist, who has a mouth speaking blasphemies against God, his name, his tabernacle, and them that dwell therein, Revelation 13:5; and the Gospel delivers men from following him, and falling in with his perverse doctrines and practices; but the word seems to be a collective one, and to be understood of all wicked men, to whom the description agrees, as it is explained in the following verses in the plural number; who out of their evil hearts, and the abundance of wickedness there, speak evil things, tending to debauch the minds and manners of others; to be delivered from whom is a singular mercy. Jarchi restrains this to heretics, and such as caused Israel to apostatize to idolatry, and turned the law into evil. The Gospel is undoubtedly a means of preserving from error and heresy.
(t) "a via mala", V. L. Pagninus, Montanus, Mercerus, Cocceius, Gejerus, Michaelis.

To deliver--as from great danger (Proverbs 6:5).
way . . . man-- (Psalm 1:1).
froward things--perversity (Proverbs 6:14; Proverbs 23:23), what is opposed to truth.

As in Proverbs 2:10, Proverbs 2:11, the אז תּבּין ("then shalt thou understand," Proverbs 2:5) is expanded, so now the watching, preserving, is separately placed in view:
12 To deliver thee from an evil way,
From the man who speaks falsehood;
13 (From those) who forsake the ways of honesty
To walk in ways of darkness,
14 Who rejoice to accomplish evil,
Delight in malignant falsehood -
15 They are crooked in their paths,
And perverse in their ways.
That דּרך רע is not genitival, via mali, but adjectival, via mala, is evident from דרך לא־טוב, Proverbs 16:29. From the evil way, i.e., conduct, stands opposed to the false words represented in the person of the deceiver; from both kinds of contagium wisdom delivers. תּהפּכות (like the similarly formed תּחבּות, occurring only as plur.) means misrepresentations, viz., of the good and the true, and that for the purpose of deceiving (Proverbs 17:20), fallaciae, i.e., intrigues in conduct, and lies and deceit in words. Fl. compares Arab. ifk, a lie, and affak, a liar. להצּילך has Munach, the constant servant of Dech, instead of Metheg, according to rule (Accentssystem, vii. 2). העזבים (Proverbs 2:13) is connected with the collective אישׁ (cf. Judges 9:55); we have in the translation separated it into a relative clause with the abstract present. The vocalization of the article fluctuates, yet the expression העזבים, like Proverbs 2:17 העזבת, is the better established (Michlol 53b); העזבים is one of the three words which retain their Metheg, and yet add to it a Munach in the tone-syllable (vid., the two others, Job 22:4; Job 39:26). To the "ways of honesty" (Geradheit) (cf. the adj. expression, Jeremiah 31:9), which does not shun to come to the light, stand opposed the "ways of darkness," the ἔργα τοῦ σκότους, Romans 13:12, which designedly conceal themselves from God (Isaiah 29:15) and men (Job 24:15; Job 38:13, Job 38:15).