The Eyes:

1. Seeing the face of the Tzaddik has the power to lift a person from depression and lethargy and free him of his evil impulses and all their ramifications (4:8).
2. The sexual appetite depends on the eyes. The tzitzit are `eyes.' The mitzvah of tzitzit is a protection and a remedy against immoral impulses (7:4).
3. Falsehood harms the eyes physically and spiritually (51).
4. Be careful not to look at people with an evil eye. The evil eye brings death to the heart of the one who has it. There are several different kinds of evil eye. Some people are filled with envy when they see the success of others. Or there may be different reasons for looking at people with an evil eye. You should be on your guard against this. You must also pray earnestly to God to protect you from being harmed by the evil eye of others. If a person feels he lacks the strength to stand up to the evil eye without being harmed, he must run away in order to escape (54:4).
5. The evil eye is the source of forgetfulness: it impairs the memory and causes one to forget one's purpose in this world, namely to acquire the World to Come. He should remember his purpose every day of his life, and fix all his thoughts on the World to Come, both as a general concept and in relation to all the particular details of his life. But the evil eye kills the heart and it can no longer be directed to the World to Come (Ibid.).
6. One with an evil eye will not have a son to survive him after his death (Ibid.).
7. You must also guard your eyes against illusions. Their source is in the image-making faculty, which gives rise to fantasy and imagination. Someone with a good eye must also guard against illusions. Even people with excellent vision can make mistakes when they look from a distance and things appear the opposite of what they really are. This is as true of the mind's eye as it is of the physical eye. For example someone may have the impression that his friend is not being honest or is behaving badly towards him. He may feel resentful in consequence and this can lead to friction. He may think that he has the highest of motives for taking issue with his friend. But the truth is that it all stems from an illusory impression. He has been led astray by his imagination, which has caused him to believe things about his friend that were fabricated and untrue. There are many other ways in which the eyes and the mind can veer from the truth because of mistaken impressions. The imagemaking faculty has the power to deceive even those who have a good eye. You must be extremely careful to avoid mistakes like this. The way to do so is by being careful not to speak badly of other people or even to listen to somebody else's malicious talk. Lashon hara, malicious gossip, gives strength to the image-making faculty and the power of illusion, and it damages the power of memory -- the power to remember at all times that this world only has meaning in terms of the World to Come (Ibid 5).
8. It is good to judge even the wicked in the scale of merit. This is the way to be saved from the evil eye of the wicked. The reason why at times the wicked go unpunished and God raises His judgements far above them is purely for the benefit of the Tzaddik. God Himself judges the wicked in the scale of merit in order to save the Tzaddik from the evil eye of the wicked (55:3).
9. When a person sees the face of the true Tzaddik he can examine himself and see what progress he is making in the various aspects of his character. Then he can repent for all the shortcomings he finds (II, 67).
10. Merely to see the true Tzaddik is in itself a great thing. Admittedly it is even better to hear Torah from his lips. But even just to see him is also very good. When a person sees the Tzaddik and looks at himself in contrast, it brings radiance to his mind and understanding, and through this he can receive greatness and attain new horizons in Torah, each individual in accordance with the power of his mind. He will achieve true modesty and humility and return to God. This is the enduring life of the World to Come (Ibid. 72).
11. Merely to see the face of the Tzaddik can help one change for the better and attain holiness (75).