Musar zu Mischlej 23:6

Miserliness is very ugly in all of its manifestations. Concerning the miser, Solomon said, "Eat thou not the bread of him that hath an evil eye" (Prov. 23:6).

It states, “Do not eat the bread of one with a miserly eye … for it is like poison in his soul” (Mishlei 23:6-7). Most people understand this: “Do not eat the bread of one with a miserly eye, for it is like poison in the soul of the host.” That is, he tries never to give of his bread to others because giving anything away is like poison to him. The Zohar (3:3a), however, gives a different explanation: “Do not eat the bread of one with a miserly eye, for it is like poison in the soul of the guest.” That is, the food that one’s receives from a miser is like poison to the receiver. Moreover, not many days will pass before he actually takes ill, sometimes dangerously so. This is why Rabbeinu HaKadosh (Rabbi Yehudah HaNasi) did not wish to accept food from anyone (Chullin 7b), for he was afraid for his life lest he benefit from a miser and then inevitably take ill. It turns out, then, that the miser causes evil both to himself and to others.