Green Tara appeared to Khenchen Tsara Dharmakirti Rinpoche (Chokyi Drakpa) while he was in a Chinese prison and gave him a prophecy that the Dharma would again flourish in Tibet:
“While he was still in prison, [Tsara Dharmakirti] Rinpoche had an auspicious vision of a pure realm where he met Green Tara. Upon seeing Green Tara, Rinpoche prayed with deep devotion and meditated on pure appearances, and suddenly a rolled piece of paper appeared in Green Tara’s hand. At first, the number seven appeared on the parchment, but as Rinpoche continued to pray, it revealed the words of a prophecy. The prophecy said that after 20 years, the Dharma would once again be able to be practiced in Tibet just as a tiny spark can be fanned into flames. The vision gave Rinpoche great courage and filled him with even stronger faith, and his practice of meditation became even more diligent as a result.
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Nearly 20 years later, Green Tara’s prophecy came to pass as in 1980 Rinpoche was able to begin teaching the Dharma to small groups of people without having to fear political consequences. In the early 1980’s, he taught at several Tibetan universities until finally in 1987 he was able to build his own shedra and retreat center in Kham Minyak. From that time on, Rinpoche began to travel to monasteries and shedras throughout Tibet once again giving teachings and empowerments. As Rinpoche grew older, he was often visited in dreams and visions by the yidam deities Tara, Yeshe Tsogyal and Kharsapana. Notably, Rinpoche received the four empowerments from Yeshe Tsogyal directly in one of these visions.
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Many miraculous signs manifested after Rinpoche’s death. After Rinpoche’s body was cremated, his bones became many-colored, glowing balls of precious medicine. The image of Tara arose from his skull cap, which did not burn in the fire. And, Rinpoche’s body expressed the sign called, ‘Tuk Jak Chen Sum’ in Tibetan, or ‘heart, tongue and eyes.’ This sign is attained by only the most superior of yogis, and was also attained by the omniscient Longchen Rabjam.”
You can read the biography of this amazing master in its entirety here.
‘Green Tara’ by Images of Enlightenment