Now is the time to grant you the initiation of the Green Hayagriva. In the time long past when the Great Bliss-Beyond-Effort, the Lotus Dancing-Master, the Lord Buddha Amida was staying in the Heaven of Aog-min[r_4:9], a vicious demon named Dregs Byod Tshogs Sprul (prideful actor multitude-conjurer) roamed the worlds (of the Cosmos), committing various evils and doing grievous harm to all sentient beings. Therefore the Lord conjured the Mandala of the Green Hayagriva, and by this subjugated the demon. Whereupon the great Mandala of Hayagriva was elaborated, the Tantra of Hayagriva preached. This caused the king of all demons great distress. In a furious mood, he raised his five burning poisons[r_4:10] and deranged the Three Kingdoms[r_4:11]. He brought contagious diseases, famine, and war to the world. He destroyed the crops and showered various weapons of destruction upon the earth. At his instigation all the demons displayed dreadful forms; plagues raged, fields were scorched, and great floods covered the corners of the earth. Evil burned continually like furious fire; both the Path of Virtue[r_4:12] and the Paths of Liberation[r_4:13] were cut; the minds of the people were oppressed; and all the sentient beings throughout the Six Lokas were thrown into immeasurable misery. Thereupon, the Bhagavan (Amida), from his heart center, sent forth the Mandala of the Wrathful Hayagriva, whereby the demon king was subjugated and bound to observe the Precepts.

By the end of the Kasyapa Buddha's[r_4:14] time in this Kalpa, the demon king Matram Rutras afflicted all the sentient beings, killing them and eating their corpses. Whereupon the Bhagavan again sent forth the Mandala of Hayagriva,

transformed in blue, and plunged it into the chest of the demon, cutting him to pieces. After the extinction of the demon, his demon-body became the abode of Hayagriva. Then he was bound by the Precepts and became known as Mahagala, the Guardian of Dharma. At that time, the Tantra of the Manifestation of the Superb Horse was preached. Later on, the Nirmanakaya Buddha, Gotama, preached the Seven Hundred Stanzas of the Enlightenment of Hayagriva.

Because of the numerous lineages of Gurus beginning with Hayagriva, preached in these sources, the well-known saying arose: "The lineages of Hayagriva are as many as the Horsehead's conjuration."

For all the sects of the Red-Cap School, a green Hayagriva in a form with four faces and eight arms was introduced also, as stated in the Tantra of Sambhuda.

This, now, is the history of Hayagriva quoted from the Treasury of Percipience: