In Vajrayana Buddhism, the Ādi-Buddha (Tibetan: དང་པོའི་སངས་རྒྱས།, Wylie: dang po'i sangs rgyas, THL: Dangpö Sanggyé) is the "First Buddha" or the "Primordial Buddha". Another common term for this figure is Dharmakāya Buddha.
The term emerges in tantric Buddhist literature, most prominently in the Kalachakra. "Ādi" means "first", such that the Ādibuddha was the first to attain Buddhahood. "Ādi" can also mean "primordial", not referring to a person but to an innate wisdom that is present in all sentient beings.
According to Anthony Tribe, this tradition may have influenced the Jñānapāda tradition of Guhyasamāja exegesis, which places Mañjuvajra (a tantric form of Mañjuśrī) at the center of the Guhyasamāja mandala.
In the Nyingma School, the Adi-Buddha is called Samantabhadra (Skt.; Tib. ཀུན་ཏུ་བཟང་པོ་, Kuntu Zangpo; Wyl. kun tu bzang po). Nyingma art often depicts this figure as a naked blue Buddha. According to Dzogchen Ponlop:
The color blue symbolizes the expansive, unchanging quality of space, which is the ground of all arisings, the basis of all appearances, and the source of all phenomena. The absence of robes symbolizes the genuine reality beyond any dualistic, conceptual, or philosophical clothing. That is the dharmakaya buddha: the genuine body of absolute truth.
According to Jim Valby (a translator of the Kunjed Gyalpo Tantra), in the Nyingma school's Dzogchen tradition, Samantabhadra ("All-Good") is not a God but "our timeless Pure Perfect Presence beyond cause and effect." In Nyingma, Samantabhadra is also considered to be the source of all Dzogchen teachings.
The Kunjed Gyalpo Tantra calls Samantabhadra the "All-Creating King" (Tib. Kunjed Gyalpo), because all phenomena are said to be manifestations or displays of Samantabhadra. According to Namkhai Norbu, this does not mean there is some being called Samantabhadra that creates the universe, instead what it refers to is that all things arise from "the state of consciousness Samantabhadra, the state of Dharmakaya." In this sense, Samantabhadra is seen as being a symbolic personification of the ground or basis (ghzi) in Dzogchen thought.
Namkhai Norbu explains that the Dzogchen idea of the Adi-Buddha Samantabhadra "should be mainly understood as a metaphor to enable us to discover our real condition." He further adds that:
If we deem Samantabhadra an individual being, we are far from the true meaning. In reality, he denotes our potentiality that, even though at the present moment we are in samsara, has never been conditioned by dualism. From the beginning, the state of the individual has been pure and always remains pure: this is what Samantabhadra represents. But when we fall into conditioning, it is as if we are no longer Samantabhadra because we are ignorant of our true nature. So what is called the primordial Buddha, or Adibuddha, is only a metaphor for our true condition.
Karl Brunnhölzl states:
Longchenpa's Treasure Trove of Scriptures...explains that Samantabhadra — one of the most common Dzogchen names for the state of original buddhahood — is nothing other than the primordial, innate awareness that is naturally free, even before any notions of "buddhas" or "sentient beings" have emerged.
In Dzogchen thought, there are said to be five aspects of Samantabhadra. Longchenpa explains these as follows:
Vesna Wallace describes the concept of Ādibuddha in the Kalachakra tradition as follows:
when the Kalacakra tradition speaks of the Ādibuddha in the sense of a beginningless and endless Buddha, it is referring to the innate gnosis that pervades the minds of all sentient beings and stands as the basis of both samsara and nirvana. Whereas, when it speaks of the Ādibuddha as the one who first attained perfect enlightenment by means of imperishable bliss, and when it asserts the necessity of acquiring merit and knowledge in order to attain perfect Buddhahood, it is referring to the actual realization of one's own innate gnosis. Thus, one could say that in the Kalacakra tradition, Ādibuddha refers to the ultimate nature of one's own mind and to the one who has realized the innate nature of one's own mind by means of purificatory practices.
"the Teacher, who is bowed to by all the Buddhas, best of the three vajras, best of the great best, supreme lord of the three vajras."
Alex Wayman notes that the Pradīpoddyotana, a tantric commentary, explains that the "three vajras" are the three mysteries of Body, Speech, and Mind, which are the displays of the Ādibuddha. Wayman further writes:
"Tsong-kha-pa's Mchan-'grel explains the "lord of body": displays simultaneously innumerable materializations of body; "lord of speech": teaches the Dharma simultaneously to boundless sentient beings each in his own language; "lord of mind": understands all the knowable which seems impossible.
According to the 14th Dalai Lama, the Ādibuddha is also seen in Mahayana Buddhism as representation of the universe, its laws and its true nature, as a source of enlightenment and karmic manifestations and a representation of the Trikaya.
In Chinese Esoteric Buddhism, and in Japanese Shingon, the Ādibuddha is typically considered to be Mahāvairocana. In Japanese Shingon, the terms Primordial body (honji-shin) and Dharmakaya principle (riho-jin) are used to refer to the Ādibuddha. It is also associated with the letter A, the first letter of the Siddham Alphabet, and is seen as the source of the universe.
The Lotus Sutra states that Sakyamuni Buddha is the "Eternal Buddha." This was the view of Nichiren, and of some modern Nichiren Buddhist schools. However, the Nikko-lineage, specifically the Soka Gakkai and Nichiren Shoshu, regard Nichiren himself as the Ādibuddha and dispute the contentions of other sects that view him as a mere bodhisattva.
In the Medieval Orissan School of Vaishnavism, Jagannath was believed to be the first Buddha avatar of Vishnu, or Adi-Buddha; with Gautama Buddha and Chaitanya Mahaprabhu being further incarnations of the Buddha-Jagannath.