The Meaning of Deity, Tsoknyi Rinpoche (may be paraphrased at times…)
…in the view of the Dzogchen, all of the appearances of samsara and nirvana never pass beyond the essence of mind…
…just because you do not see something, it is not right to think that it does not exist. Buddha stated that until you reach Buddhahood, your various sense faculties are not valid cognizers of what lies outside their realm of operation…
…Deities and so forth do exist; it would be wrong to say that they do not. Still, you need to have a way to connect with them. To connect with them, the thing that you need is direct perception of the essence of mind in its emptiness aspect… that emptiness is not merely empty but also has a radiance aspect to it, and it is this radiance aspect which appears as deities.
… Thus it is not a waste of time to do the practices involving deities because the deities do exist but it is equally true that you need to know how they exist so that you can connect with them properly. If you were to think that they exist in a really true, solid way, you would never be able to connect with them. The same is true if you have a very solid desire to meet them, thinking, “I want to connect with them!” that is just another form of grasping and will get in the way of connecting with them properly.
…Deities are insubstantial yet not non-existent…If you think that the deities do not exist, you have fallen into the view of nihilism and, conversely , if you think that they do exist, you have fallen into eternalism. Deities are beyond extremes.