The importance of Nirvana in Buddhist thought cannot be fully understood without the context from which it emerged. The Buddha, like all religious teachers from his region of the world during the Axial Age, was chiefly concerned with liberation. The wheel of time, having always turned according to the law of karma, passes conscious beings through countless lives, some beings birthed with knowledge of their prior lives and others without. Birth is either a blessing or curse. A blessing, because it provides a new chance to understand reality and escape rebirth. A curse, because a birth implies a failure in the prior life to understand reality–to achieve Nirvana (or Moksha, as the concept was known in earlier and contemporary Vedic and non-Vedic traditions in India).
Nirvana, meaning “extinction,” represents the escape from the cycle of rebirth. At the risk of overgeneralizing, the Mahayana and non-Mahayana schools represent two poles on a spectrum. In the non-Mahayana, the concept of Nirvana is purely defined as a negative. For the non-Mahayana, Nirvana is withdrawal from, an escape from, a cessation, an obliteration. Although, the Pali Canon does contain some positive descriptions of Nirvana,1 the Canon largely explains Nirvana according to what it is not, aa in “a state beyond cause and effect as it is beyond good and evil.”2 In the non-Mahayana, there are two types of Nirvana: nirvana with a remainder of conditionality, which is attained before death, and nirvana without conditionality, which is attained at death.
For the Mahayana, Nirvana takes on a positive aspect. The Buddha-nature within all sentient beings is a light which is obscured and must discovered. The Dharma body emanates a variety of forms to beckon ignorant and misguided beings towards liberation.
1Padhi & Padhi, 1990, 144.
2Padhi & Padhi, 1990, 144.