Yea also, when he that is a fool walketh by the way,.... The king's highway, the common road; as he passeth along the streets, going to any place, or about any business:his wisdom faileth [him]; or "his heart" ; he appears by his gait, his manner of walking, to want a heart, to be a fool; walking with a froward mouth, winking with his eyes, speaking with his feet, and teaching with his fingers; all which shows the frowardness and folly of his heart, Pr 6:12; or he discovers it throughout his conversation, in all the actions of it, in whatsoever business he is concerned, and in all the affairs of life.
The Targum is,"when he walketh in a perplexed way;''then his wisdom fails him; he does not know which way to take, whether to the right or left: this can never be understood of the highway of holiness, in which men, though fools, shall not err, Isa 35:8;and he saith to everyone [that] he [is] a fool; his folly is manifest to all; he betrays it, by his words and actions, to every man he has to do with; his sins and transgressions, which are his folly, he hides not, they are evident to all; and, as the Targum expresses it,"all say he is a fool:''though indeed he himself says this of every other man, that he is a fool; for, according to the Vulgate Latin version, he, being a fool himself, thinks everybody else is so.