Deity Yoga

At the beginning of the process of deity meditation and mantra repetition one meditates on emptiness, settling the non-inherent existence of oneself and the deity through a reasoning such as that of dependent-arising--the fact that both oneself and the deity arise in dependence on their respective bases of designation. One's own final nature and the final nature of the deity are the same, an emptiness of inherent existence.

To perform deity yoga one does not just withdraw ordinary appearances and then appear as a deity but causes the mind realising emptiness itself to appear as a deity. Thus, it is essential initially to meditate on emptiness, cleansing all appearances in emptiness. One then uses that wisdom consciousness realising emptiness as the basis of emanation of a divine body. This must be done at least in imitation of a consciousness actually doing this, for meditation on a truly existent divine body, instead of helping, will only increase adherence to inherent existence. Meditated properly, the appearance of a divine figure is the sport of the ultimate mind of enlightenment, first in imitation and later in fact. (p.39)

--from Deity Yoga in Action and Performance Tantra by His Holiness the Dalai Lama, Tsong-ka-pa, and Jeffrey Hopkins, published by Snow Lion Publications
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