"Vairocana Buddha preached extensively for two weeks the meaning of this [mind], after having attained enlightenment for the first time, to the great Bodhisattva Samantabhadra and to others. He was residing, as it were, in a lotus-adorned abode of glorious enlightenment in the country called the World of Dharma. He manifested himself in seven places and held eight assemblies to unfold the Avatamsaka Sutra. He first entered the concentration known as the sagaramudra samadhi and meditated on the complete diffusion of the Nature of Dharma (dharmata). (p. 212 - 213)
The reference to the Avatamsaka Sutra links this mind to the Hua-yen (Kegon in Japanese) School of Buddhism.
(Quotations are from "Kukai: Major Works", Hakeda, 1972)
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