is a Buddhist holiday exclusively celebrated in Japan during both the Spring and Autumnal Equinox

Equinox

An equinox occurs twice a year, when the tilt of the Earth's axis is inclined neither away from nor towards the Sun, the center of the Sun being in the same plane as the Earth's equator...

. It is observed by nearly every Buddhist sect in Japan. The tradition extends from mild weather that occurs during the time of equinoxes, though the origin of the holiday dates from Emperor Shomu

Emperor Shomu

was the 45th emperor of Japan, according to the traditional order of succession.Shōmu's reign spanned the years 724 through 723.-Traditional narrative:...

 in the 8th century. People who normally worked in the fields had more leisure time to evaluate their own practices, and to make a renewed effort to follow Buddhism. Today, special services are usually observed in Japanese Buddhist temples, and Japanese temples abroad, based on the particular Buddhist tradition or sect.

The etymology of higan means "the other or that shore of Sanzu River

Sanzu River

The Sanzu River , or River of Three Crossings, is a Japanese Buddhist tradition and religious belief similar to the River Styx...

", which is a common euphemism used in Buddhist literature to refer to Enlightenment

Enlightenment in Buddhism

The English term enlightenment has commonly been used in the western world to translate several Sanskrit, Pali, Chinese and Japanese terms and concepts, especially bodhi, prajna, kensho, satori and buddhahood.-Insight:...

. One crosses from this shore of ignorance

Ignorance

Ignorance is a state of being uninformed . The word ignorant is an adjective describing a person in the state of being unaware and is often used as an insult...

 and suffering

Suffering

Suffering, or pain in a broad sense, is an individual's basic affective experience of unpleasantness and aversion associated with harm or threat of harm. Suffering may be qualified as physical or mental. It may come in all degrees of intensity, from mild to intolerable. Factors of duration and...

 to the other shore of Enlightenment and peace. In the Alagaddupama Sutta (MN 22) of the Pali Canon

Pāli Canon

The Pāli Canon is the standard collection of scriptures in the Theravada Buddhist tradition, as preserved in the Pāli language. It is the only completely surviving early Buddhist canon, and one of the first to be written down...

 the Buddha uses a simile of a person constructing a raft to cross one shore to the other, symbolizing realization or Enlightenment. In the Heart Sutra

Heart Sutra

The Heart Sūtra is a Mahāyāna Buddhist sūtra. Its Sanskrit name literally translates to "Heart of the Perfection of Transcendent Wisdom." The Heart Sūtra is often cited as the best known and most popular of all Buddhist scriptures.-Introduction:The Heart Sūtra is a member of the Perfection of...

 of Mahayana

Mahayana

Mahāyāna is one of the two main existing branches of Buddhism and a term for classification of Buddhist philosophies and practice...

 Buddhism is the mantra:

gate gate pāragate pārasaṃgate bodhi svāhā

Gone, gone, gone beyond, everyone gone beyond [to the Other Shore], Enlightenment Hail

Emphasis on Ohigan is the teaching of the Six Perfections

Paramita

Pāramitā or pāramī is "perfection" or "completeness." In Buddhism, the pāramitās refer to the perfection or culmination of certain virtues...

, as well as a renewed resolve to reach Enlightenment.