Also known as: Dainichi-kyo

An important Buddhist sutra used in esoteric schools of Buddhism, especially the Shingon sect. This sutra is unusual in that it did not originate from Shakyamuni Buddha, the founder of Buddhism, but was said to have passed straight from Mahavairocana Buddha. It was brought to Japan by Kuukai.

In this sutra, Mahavairocana translates his teachings into ritual forms which form the basis of the rituals in the Shingon School.

Also known as: Suryaprabha

Lit.: "Sunlight/Solar Radiance Bodhisattva", a bodhisattva whose whose specialty is sunlight and good health, often seen with her sister Gakkou Bosatsu, the Moonlight Bodhisattva, with whom she serves Yakushirurikou Nyorai, the Medicine Buddha. They are also sometimes attendants of Kannon.

At the Toudai Temple in Nara, she stands to the right of Fukuukenjaku Kannon.

The Niou guardians, literally called the 'Benevolent Kings', are commonly seen at the doors of temples and guard those within from demons and evil spirits. The Agyou (阿形), who utters the syllable 'a', stands with his mouth open, while the Ungyou (吽形), who utters the syllable 'un', stands with his mouth closed.

A low box-type seat made of lacquered wood placed in front of the altar on which priests sit to perform religious ceremonies.

Also known as: Roku Dou Kai (六道界), Roku Dou (六道)

Lit. "Six Path Worlds" or just "Six Paths"; a Buddhist belief stemming from Hinduism which says that all beings are trapped within a cycle of life and death and are born into one of six realms until they are enlightened and can break free from the cycle. The six realms are: Jigoku Dou, Gaki Dou, Chikushou Dou, Ashura Dou, Nin Dou, and Ten Dou.

Lit.: River of Three Crossings

The Sanzu river is the Japanese Buddhist equivalent of the River Styx, which the Japanese believe the dead must cross on the seventh day after their death. The crossing can be easy or difficult depending on the deeds performed by the deceased during their lifetime.

The riverbed of the Sanzu no Kawa is reserved for unfilial children who die before their parents, thereby causing their parents great sorrow. This place is called the Sai no Kawara (賽の河原), or "Children's Limbo." The child is condemned to remain there to build a tower of stones, pebble by pebble, for the memorial service of his or her parents, but the pagoda is knocked down by a demon before it can completed, and the child must begin again. The cycle continues until the child is finally saved by the Kṣitigarbha bodhisattva.

There are many Sai no Kawara sites located throughout Japan where grieving parents go to pray for the soul of their child and to console their own sorrow, that their child may rest. One of these which goes back to at least 1658 is located on the bank of Lake Ashi in Motohakone, at the foot of the shrine gate of Hakone Shrine.

A sect ("True Word") of Esoteric Buddhism with around 3000 temples and 5000 priests through Japan, founded by Kuukai. Its teachings are based on the Mahavairocana and Vajrasekhara Sutras.

Also known as: Seishoku Daikongou Yasha (青色大金剛薬叉)
Lit.: Blue-Faced Vajra

A deity of healing who protects against disease. He is ruler of the East and is pictured as an angry deity with blue skin (due to taking the diseases of others into himself) and four or six arms holding, variously, a vajra, a ritual staff, a wheel (symbolizing Buddha's teachings), and a noose (symbolizing the triumph of Buddhism over evil). He is a fierce protector of Buddhism and repels the calamities of evil beasts, diseases, and thunder.

Due to his healing powers, he became associated with the rituals of the Koushin beliefs.

Also known in Sanskrit as 'bīja' or 'seed', these 'seed syllables' are thought to be connected to spiritual principles in Esoteric Buddhism and are used in mantras. Bai is one example.

A sutra which was once considered a national treasure of India, it was secretly brought to China and translated in 705. Also called the "Sutra of the Heroic One", it gives the most detailed explanations of the teachings of the Buddha regarding the mind, including the workings of of karma, a description of the realms of existence, ways to enlightenment, etc. It is said that every existing Dharma can be found in this sutra. The word "Shurangama" is translated as "ultimately firm and strong."

Lit. "Path of Heaven"; the highest realm of the Six Realms of Buddhism: celestial beings who hold god-like powers and live in happiness and pleasure for countless ages, but who will still eventually die because they are too filled with pride to reach enlightenment.

Also known as: Divyadundubhimeghanirghoṣa

One of the Five Wisdom Buddhas of the Womb Realm whose name means 'he who makes the drum of the sky resound like thunder'. He is the Buddha of the North

The last letter of the Sanskrit alphabet, pronounced with the mouth closed. Represents omega, ending, and exhalation.

Also known as: kongou-sho (金剛杵)

A mystical indestructible weapon in Buddhism and Hinduism which destroys ignorance. In Hindu mythology, this weapon was made out of the spine of the sage Dadhichi, who sacrificed himself so that this weapon could be created to kill Vitrasur, who had conquered heaven and terrorized gods.

In tantric rituals, the vajra, held in the right hand, symbolizes the male principle while the bell, held in the left hand, symbolizes the female principle; their interaction leads to enlightenment.

The Womb Realm, based on the Mahāvairocana Tantra, is the metaphysical space inhabited by the Five Wisdom Buddhas. Its name comes from chapter 2 of the sutra, which states that the buddha Mahāvairocana (Dainichi Nyorai) revealed the mandala's secret teachings to his disciple Vajrasattva (Kongousatta) from his "womb of compassion".

The Womb Realm mandala, along with the Diamond Realm mandala, form the core of Tendai and Shingon Buddhist rituals and are usually hung on the east and west walls of Shingon temple halls.

In depictions of the Womb Realm, Mahāvairocana sits at the center of an eight-petaled lotus wearing a jewelled crown. Four Buddhas representing the four directions, Ratnaketu (Houtou Nyorai), Saṃkusumitarāja (Kaifukeou Nyorai), Amitābha (Amida Nyorai), and Divyadundubhimeghanirghoṣa (Tenkuraion Nyorai), are placed orthogonal to Mahāvairocana. Four bodhisattvas, Samantabhadra (Bugen Bosatu), Manjushri (Monju Bosatsu), Guanyin (Kannon), and Maitreya (Miroku Bosatsu), are illustrated between the Buddhas.

Hundreds more divinities reside in eleven more halls branching from the center.