“turning away.” The Hebrew is meshuwbah (#04878 מְשׁוּבָה) and it occurs 13 times in the OT, with all the occurrences in Jeremiah and Hosea except this verse in Proverbs. In the prophets it referred to Israel turning away from God and the Covenant they made to keep His laws. Here in Proverbs the simple one, a naïve and foolish person, turns away from wisdom, the right way, etc. It seems that because in Proverbs it is the simple one who turns away that it is not referring to someone who sets out to do evil, rather it is the simple person who gives no thought to his way and just follows every emotion and inclination. In fact, he could wander back and forth between truth and error if that was how he felt at the moment (cp. “aimless wandering” CJB by D. Stern). He does not “turn” from his way to follow wisdom (Prov. 1:23), but “turns away” from wisdom and what is right, and ends up dead—eternally dead, but sometimes even coming to a premature death on earth. Such grave consequences! God created us and expects us to love and obey Him. If we are too foolish to do that, we “eat the fruit of our own way” (Prov. 1:31). We could see “turning away” as a personification here, although it is a weak one, because “turning away” kills the person.
“false security.” The Hebrew word is shalvah (#07962 שַׁלְוָה), and it means quietness, ease, rest, security, unconcern, or prosperity. It can refer to a feeling of security, or a feeling of false security. Here it refers to the feelings of false security that the fool has, not seeing the dangers of life or his responsibility to God and man, he does not see disaster coming. The ASV says, “careless ease,” and fools certainly have that too. Other versions read ‘complacency,” which means “an inclination to please,” and does not seem to fit the profile of most fools.