Some people, more often men, spend their entire lives awash in bitterness. They rage against injustices done to their forefathers, perhaps centuries in the past. They rage against injustices done to their countrymen, their families. They rage against people who are unlike themselves, who, by virtue of their difference, must be up to no good. They rage against people who are like themselves who do not share their views. They rage against their parents, their wives, their children, and against anyone who is sympathetic to any of these. Their rage is a screen between them and the world, behind which they huddle over their egos, like a caveman over his fire, unable to see out through the smoke.

What is anger? A lust for revenge. What is hatred? An anger grown old.

Usually, if we hate, it is the shadow of the person that we hate, rather than the substance. We may hate a person because he reminds us of someone we feared and disliked when younger; or because we see in him some gross caricature of what we find repugnant in ourself; or because he symbolizes an attitude that seems to threaten us.

The people you hate, well, this is the question about such people: why do you hate them?

Anger — a passion of displeasure that may be excessive or misplaced but not necessarily harmful. Hatred — an emotional habit or attitude of mind in which aversion is coupled with ill will. Anger, used, does not destroy. Hatred does.

In the end, rage, no matter how profoundly justified, destroys the enraged. Just as we are created anew by what we love, so we are reduced and unmade by what we hate.

Despite all the positive psychological attributes of hatred we have outlined, hatred destroys finally the core of the life of the hater. While it lasts, burning in white heat, its effect seems positive and dynamic. But at last it turns to ash, for it guarantees a final isolation from one’s fellows. It blinds the individual to all values of worth, even as they apply to himself and to his fellows. Hatred bears deadly and bitter fruit. It is blind and nondiscriminating.

These are the people who hate themselves because they haven't come to terms with their helplessness. They feel threatened by helplessness itself, not by those who caused or reinforced the feeling, and this is what produces their boundless rage. Therefore, they repress their helplessness, which has made them feel rejected and despised, at the same time oppressing their 'oppressors' contempt for them.

It’s easy to forgive people who have never done anything to make us angry. People who do make us angry, however, are our most important teachers. They indicate the limits to our capacity for forgiveness. “Holding grievances is an attack on God’s plan for salvation.” The decision to let go our grievances against other people is the decision to see ourselves as we truly are, because any darkness we let blind us to another’s perfection also blinds us to our own. It can be very hard to let go of your perception of someone’s guilt when you know that by every standard of ethics, morality, or integrity, you’re right to find fault with them. But the Course asks, “Do you prefer that you be right or happy?

Hatred is a curse that does not affect the hated. It only poisons the hater. Release a grudge as if it were a poison.

Hatred is like a long, dark shadow. Not even the person it falls upon knows where it comes from, in most cases. It is like a two-edged sword. When you cut the other person, you cut yourself. The more violently you hack at the other person, the more violently you hack at yourself. It can often be fatal. But it is not easy to dispose of. Please be careful, Mr.Okada. It is very dangerous. Once it has taken root in your heart, hatred is the most difficult think in the world to shake off.

There's another reason why you should love your enemies, and that is because hate distorts the personality of the hater. We usually think of what hate does for the individual hated or the individuals hated or the groups hated. But it is even more tragic, it is even more ruinous and injurious to the individual who hates. You just begin hating somebody, and you will begin to do irrational things. You can't see straight when you hate. You can't walk straight when you hate. You can't stand upright. Your vision is distorted. There is nothing more tragic than to see an individual whose heart is filled with hate. He comes to the point that he becomes a pathological case. For the person who hates, you can stand up and see a person and that person can be beautiful, and you will call them ugly. For the person who hates, the beautiful becomes ugly and the ugly becomes beautiful. For the person who hates, the good becomes bad and the bad becomes good. For the person who hates, the true becomes false and the false becomes true. That's what hate does. You can't see right. The symbol of objectivity is lost. Hate destroys the very structure of the personality of the hater. [...] when you start hating anybody, it destroys the very center of your creative response to life and the universe; so love everybody. Hate at any point is a cancer that gnaws away at the very vital center of your life and your existence. It is like eroding acid that eats away the best and the objective center of your life. So Jesus says love, because hate destroys the hater as well as the hated.

Holding anger is a poison. It eats you from inside. We think that hating is a weapon that attacks the person who harmed us. But hatred is a curved blade. And the harm we do, we do to ourselves.

Another reason why we must love our enemies is that hate scars the soul and distorts the personality. Mindful that hate is an evil and dangerous force, we too often think of what it does to the person hated. This is understandable, for hate bring irreparable damage to its victims. We have seen its ugly consequences in the ignominious deaths brought to six million Jews by a hate-obsessed madman named Hitler, in the unspeakable violence inflicted upon Negroes by blood-thirsty mobs, in the dark horrors of war, and in the terrible indignities and injustices perpetrated against millions of God's children by unconscionable oppressors. But there is another side which we must never overlook. Hate is just as injurious to the person who hates. Like an unchecked cancer, hate corrodes the personality and eats away its vital unity. Hate destroys a man's sense of values and his objectivity. It causes him to describe the beautiful as ugly and the ugly as beautiful, and to confuse the true with the false and the false with the true.