Perfection Stage

Deity yoga (Tibetan: lha'i rnal 'byor; Sanskrit: Devata-yoga) is the fundamental Vajrayana practice. It involves two stages, the generation stage and the completion stage. In the generation stage, one meditates on the yidam, resulting in identification woth this yidam. In the completion stage, one engages Kundalini yoga practices, and dissolves the visualition of and identification with the yidam in the realisation of sunyata, emptiness.

The purpose of Deity yoga is to bring the meditator to the realization that the deity and the practitioner are in essence the same, non-dual. The yidam generally appears in a mandala and the practitioner visualizes himself or herself and their environment as the yidam and mandala of their Deity Yoga practice. This visualization method undermines a habitual belief that views of reality and self are solid and fixed, enabling the practitioner to purify spiritual obscurations (Sanskrit: klesha) and to practice compassion and wisdom simultaneously:

Deity Yoga employs highly refined techniques of creative imagination, visualisation, and photism in order to self-identify with the divine form and qualities of a particular deity as the union of method or skilful means and wisdom. As His Holiness the Dalai Lama says, "In brief, the body of a Buddha is attained through meditating on it".

Representations of the deity, such as a statues, paintings (Tibetan: thangka), or mandalas, are often employed as an aid to visualization in both the Generation Stage (Tibetan: Kye-rim) and the Completion Stage (Tibetan: Dzog-rim) of Anuttarayoga Tantra. The mandalas are symbolic representations of sacred enclosures, sacred architecture that house and contain the uncontainable essence of a yidam. In the book, The World of Tibetan Buddhism, the Dalai Lama describes a mandala: “This is the celestial mansion, the pure residence of the deity.”

In the Vajrayāna Buddhism of Tibet and East Asia, which follow the Nālandā Tradition of India-Tibet-China, there are fifteen major tantric sādhanās, each connected with a specific yidam:

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