מוסר אויף קהלת 2:14

The simple understanding of the verse is that the commandment is like a lamp to give off light in front of you, as it is written, the commandment of the Lord is lucid, making the eyes light up (Psalms 19:9); w,hereas Torah is a light to those that study it, while a fool walks in darkness [alluding to Ecclesiastes 2:14]. But behold there are two understandings of a lamp and a light. The first is that a single lamp is called a lamp, whereas a light is a big torch. And this agrees with what the sages, may their memory be blessed, gathered about and decided (Kiddushin 40b), "The study of Torah is greater, as it leads to action." It called a commandment, which is an action, a lamp; and the Torah, which is study, a light. A second understanding is that in the lamp itself, the light is connected to the lamp. For the lamp is the receptacle of the light, meaning the candle or the wick in the oil in a vessel, and the light holds on to it. So they cling to one another and need one another. For the light of the lamp does not have anything to hold on to without the lamp, since the existence of the light, without something to hold onto, returns to its original source [and becomes latent]. The lamp also does not have any luminescence without the light that holds onto it.

Therefore he whose eyes are on his head (Kohelet 2:14), should be more watchful to scrutinize the deeds of someone who he wishes to acquire as a friend, advisor, or workers over his household than he is watchful to scrutinize his food and drink. For his food and drink can only damage his body while his friends and workers can destroy his soul, belongings and all of his honor. King David peace be unto him said: "He will not dwell within my house, he who practices deceit. He who follows the way of the innocent, he will serve me" (Tehilim 101:6-7).