Verse 6 - If a rich man or woman who has always been miserly toward you suddenly invites you to dinner, it is wise to decline the invitation. Such a person is not offering friendship or his approval of you for the sake of friendship, but rather probably desires to use expensive food to manipulate you. An "evil eye" means that one is only interested in "eyeing others up" for selfish or evil purposes. This kind of person will use entertainment to entice people to give them what they want. Their desires might range from sex, property, business influence, or a position you have that they covet. A safeguard against falling prey to one with an evil eye, is not to love the things in this world and not to follow after those given to the lusts of the flesh (appetite), or eyes (desire), or the pride of life. Then we will not be susceptible to their manipulations.
"Love not the world, neither the things that are in the world. If any man love the world, the love of the Father is not in him. For all that is in the world, the lust of the flesh, and the lust of the eyes, and the pride of life, is not of the Father, but is of the world. And the world passeth away, and the lust thereof: but he that doeth the will of God abideth for ever" (1 John 2:15).
Verse 7 - Jesus verified that "as a man thinks in his heart, so is he." Thieves, slanderers, and lovers of money express in words and deeds the evil in their hearts. "And Jesus said, Are ye also yet without understanding? Do not ye yet understand, that whatsoever entereth in at the mouth goeth into the belly, and is cast out into the draught? But those things which proceed out of the mouth come forth from the heart; and they defile the man. For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies: These are the things which defile a man: but to eat with unwashen hands defileth not a man" (Matthew 15:16-20). An "evil eye" describes the attitude of a man who cares more about his money than his friends. He may invite you to dine with him, serving gourmet food and urging you to enjoy yourself only for the sake of appearances. If, in his heart, he begrudges the cost of entertaining you, he is no true friend. Your time with such a person is wasted. Friendship does not flourish where the host calculates with misgivings the expense of what his guest consumes.
Verse 8 - This kind of meal will end up making you sick, and all the seemingly "good time" and "sweet words" will have been in vain. We are warned not to get trapped into circumstances like this. We will end up regretting it if we do.