47 The Hiphil infinitive construct of נָצַל (natsal, “to deliver”) expresses the purpose of understanding right conduct: to protect a person from the wicked. The verb נָצַל (natsal) means “to save; to deliver; to rescue,” as in snatching away prey from an animal, rescuing from enemies, plucking a brand from the fire, retrieving property, or the like. Here it portrays rescue from the course of action of the wicked.
48 The term “wicked” (רַע, ra’) means “bad, harmful, painful.” Rather than referring to the abstract concept of “wickedness” in general, the term probably refers to wicked people because of the parallelism with “those speaking perversity.”
49 Heb “man.” The singular noun אִישׁ (’ish, “man”) here will be further defined in vv. 13–15 with plural forms (verbs, nouns and suffixes). So the singular functions in a collective sense which is rendered in a plural sense in the translation for the sake of clarification and smoothness.
50 Heb “perversities.” The plural form of תַּהְפֻּכוֹת (tahpukhot) may denote a plurality of number (“perverse things”) or intensification: “awful perversity.” As here, it often refers to perverse speech (Prov 8:13; 10:31, 32; 23:33). It is related to the noun הֶפֶךְ (hefekh, “that which is contrary, perverse”) which refers to what is contrary to morality (Isa 29:16; Ezek 16:34; 246 הֶפֶךְ). The related verb הָפַךְ (hafakh, “to turn; to overturn”) is used (1) literally of turning things over, e.g., tipping over a bowl (2 Kgs 21:13) and turning over bread-cakes (Judg 7:13; Hos 7:8) and (2) figuratively of perverting things so that they are morally upside down, so to speak (Jer 23:36). These people speak what is contrary to morality, wisdom, sense, logic or the truth.