Today, the 28th day of the fourth lunar month, is the birthday of Bhaiṣajyarāja Bodhisattva, the Medicine King Bodhisattva. Innumerable and incalculable eons ago, the Buddha tells the story of a 'Medicine King' Bodhisattva, who made great vows to a Buddha in a previous life.
The story goes:
Innumerable and incalculable eons ago, there was a Buddha with the honorary title Lazuli Light Illumination Tathāgata. After his parinirvāṇa during the Period of Semblance Dharma (saddharmapratirūpaka), a thousand bhikṣus who have developed Bodhicitta roamed the world to edify living beings. Among them there was a bhikṣu with the Dharma name Sun-Store; he often told the stories that praised Mahāyāna bodhisattvas to the Buddhist assembly and expounded anuttarasamyaksaṃbodhi (unsurpassed, complete, and perfect enlightenment).
Among the members of the assembly, there was an elder whose name was Star-Light. Upon hearing about the Buddha’s unsurpassed, complete, and perfect enlightenment, he was greatly rejoiced in his heart, so he brought rare wonderful medicine of the snow-capped mountains to Bhikṣu Sun-Store and offered it to the saṃgha, while making great vows,
“I have heard from you the Dharma wisdom, the excellent medicine, which is completely true. Now I offer the excellent medicine of the snow-capped mountains to you and the saṃgha. I wish to dedicate, with a correct mind, the merits accrued from this deed to the attainment of anuttarasamyaksaṃbodhi, without ever intending to pursue karmic rewards in the human and heavenly realms. Now with utmost sincerity, I resolve to seek the supreme perfect enlightenment and will surely attain Buddhahood in the future.”
The elder also vowed,
“After I realize the pure Bodhicitta, though I am not a Buddha yet, living beings who hear my name will be free from three kinds of sufferings. First, as long as sentient beings chant my name, they will be able to dispel and recover completely from 440 diseases that exist in their bodies. Second, they will never suffer from wrong views and ignorance nor experience the sufferings of the three miserable realms; when I attain Buddhahood, all beings born in my land will be able to realize equal Mahāyāna. Third, living beings in Jambudvīpa and in other places with the three miserable realms, when they hear my name, will never be reborn in the miserable realms; if a single one of them falls into the miserable realms, I will not be able to attain anuttarasamyaksaṃbodhi.”
With the power of the medicine offered by Elder Star-Light, everyone in the assembly developed the aspiration for attaining anuttarasamyaksaṃbodhi; they exclaimed jubilantly, “We all will attain Buddhahood in the future!” They said to each other, “Thanks to the two types of excellent medicine offered by this great bodhisattva, we successfully developed the aspiration for attaining Buddhahood and will become the king of the Great Chiliocosm. To repay his kindness, we should set up a title of honor for him. Because of his great deed of offering medicine, we should call him Medicine King.”
The elder Star-Light at that time is the present-day Bhaiṣajyarāja Bodhisattva. He is said to have been reborn over a period of numerous lifetimes healing and curing diseases, and is a representation of the healing power of the Buddha. Together with Supreme Medicine Bodhisattva, Sunlight Radiance Bodhisattva, Moonlight Radiance Bodhisattva, and the Twelve Great Yaksa Generals, he forms the retinue of Lapis-lazuli Medicine Buddha (Bhaishajyaguru).
The bodhisattva made excellent virtuous vows
to offer medicine and benefit all beings.
He will become a Buddha in the future,
with the honorary title Pure Eye.
By extensively delivering human and heavenly beings
out of infinite loving-kindness,
He shines upon all with the eye of wisdom
and will eventually attain Buddhahood.
— Sūtra Spoken by the Buddha on Visualizing the Two Bodhisattvas Bhaiṣajyarāja and Bhaiṣajyasamudgata