The Dharmakaya ( unfabricated and uncorrupted view), Emptiness.

When you listen to teachings, you should generate the bodhicitta mind, the desire to obtain Buddhahood for the sake of others. This seems difficult, but whatever practice you do should be based on that attitude.

Even though it seems a bit artificial, you should try to have that attitude. If you do that, your practice will generate a great deal of virtue, because your practice will not be aimed for your own benefit. This is so even if the bodhicitta is not genuine. Many people confuse loving kindness and compassion with bodhicitta.

The attitude you should take is that first I will attain enlightenment so that I can lead all beings to enlightenment. We all have buddha nature. It is our fundamental mind and is originally pure.
We have many different consciousness, such as the five sense consciousnesses and the sixth mental consciousness.

These are like clouds in the sky covering our fundamental mind. Dharmakaya has two purities. Originally mind is pure. It is like gold that is hidden in the earth as ore. As we practice our negative thoughts will occur less and eventually they will be extinguished. When they are extinguished, that is the second purity.

So one purity is by nature and one is through our efforts.
The two purities are called the svabhavivakaya. The wisdom is called jnanakaya. Their union is the dharmakaya. The purity and wisdom are inseparable in the dharmakaya. Dharmakaya always has wisdom.

When the negativities are eliminated then our wisdom will manifest.
The dharmakaya cannot be spoken about or thought about, although here I am doing that. There are many great Indian and Tibetan scholars who have written down their understanding so we can have some idea of even though we haven't experienced it. There are many analogies for dharmakaya.

One is deep sleep without dreams. In the daytime we have many thoughts and activities. But in dreamless sleep all of these are gone. Dharmakaya is beyond all conceptions. Another analogy is the death state. At the time of death the five elements dissolve. That state is close to the dharmakaya. Only the mental continuum remains. One goes through the stages of the white appearance, the red appearance, and the dark appearance and emerges in a state that resembles the dharmakaya.

Another analogy used is a finger pointing to the moon. The various teachings are like a finger pointing to the moon. At the end of deity meditations, one dissolves the meditation into emptiness. This is an attempt to approach the dharmakaya.
The sambhogakaya manifests from the dharmakaya. It is like the dreaming state. Even the highest level bodhisattvas cannot directly access the dharmakaya, but they can access the sambhogakaya and receive teachings from it. Ordinary beings cannot receive teachings from the bodhisattvas.

So the nirmanakaya manifests, like the Buddha being born in India. The nirmanakaya is like the waking state.
At the time of death whatever deity you have practiced will appear to you in a dream. If you recognize the deity, you will not be reborn in the six samsaric realms. In the lower tantra you and the deity are separate and you beseech the deity. In the higher tantras there is no separation.
Chokyi Goecha