Suffering related to the universe and its inhabitants are the result of false perceptions, the nature of which it is important to understand. Emotions, such as attachment, anger and ignorance are all creations of the mind. We think, for instance, of our body as a precious possession of which we must take special care, protecting it from illness and every kind of mishap. We get into this habit of thinking and, as a consequence, begin to suffer mentally as well as physically. This is an example of perception which, since it is devoid of any basis in reality, it is called deluded; it depends upon the belief in the existence of something which does not exist at all. It is just as when we dream and think that we are being burned or drowned, only to discover, when we wake up, that nothing has happened.
From the view of absolute truth, phenomena have no actual entity. What we think of as 'I', 'my body', my 'mind', 'my name', have no real existence. Other beings have no real existence either, whether they be dangerous enemies or loving parents. In the same way, the five poisons are by nature empty. Bearing this fact in mind, we should watch for where these poisons, these negative emotions arise, what does the agent of these arisings look like, and what do the emotions themselves look like? If we analyse, we shall find nothing. This absence is the unnborn Dharmakaya.
Although everything is by nature empty, this emptiness is not the mere vacuity of empty space or an empty vessel. Happiness, sufferings, all sorts of feelings and perceptions appear endlessly like reflected images in the mind. This reflection-like appearance of phenomena is called the Nirmanakaya.
A grain not planted in the soil will never give a fruit, likewise that which is unborn will never cease to be. To be beyond origination is to be beyond cessation also. This aspect of unceasingness is what should be understood as Sambhogakaya.
If there is neither birth, in the past, nor cessation, in the future, there cannot be something which endures in the present; for an existence necessarily implies a beginning and an end. For example, though it might be thought that, while we are alive, the mind resides in the body, in fact there is no residing and no one who resides; there is no existence and nothing that exist. Even if one were to seperate the skin, the flesh, the muscles and the blood, of the body, where would the mind be found? Is it in the flesh or in the bone, etc? Nothing will be found, for the mind itself is void. The fact that the mind is by nature empty, that it is nevertheless the place where phenomena appear, and that it is beyond origination and is therefore unceasing-this inseperable union of the three kaya is called Svabhavikakaya.
If deluded perceptions are understood in terms of the four kayas, it follows that in that which is termed deluded, there is nothing impure, nothing to rid itself of. Neither is there something else, pure and undeluded, which we should try to adopt. For, indeed, when illusion dissolves, undeluded wisdom is simply present, where it always has been. When gold is in the ground, for example, it is blemished and stained; but the nature of gold as such is not susceptible to change. When it is purified by chemicals or refined by a goldsmith, its real character increasingly shines forth. In the same way, if we subject the deluded mind to analysis, and reach the conclusion that it is free from birth, cessation and abiding existence, we will discover, then and there, a wisdom which is undeluded. Furthermore, the deluded mind, being itself illusory, is unstable and fluctuates, like experiences in a dream, whereas the true and undeluded nature of phenomena, the Buddha-nature or Tathagatagarbha, has been present from unoriginated time. It is exactly the same in ourselves as it is in the Buddhas. It is thanks to it that the Buddhas are able to bring help to beings; it is thanks to it, too, that beings may attain enlightenment. There is no other introduction to the four kayas than this understanding of the true nature of illusory perception.
-H.H. Dilgo Khyentse Rinpoche,
excerpted from Enlightened Courage