The 2nd major Honzon deity of the 88 important Shikoku Island temples is called (in Japanese) Yakushi Nyorai and it is named Bhaisajyaguru in the Sanskrit language. In the Japanese language, he is named Yakushi Ruriko Nyorai. In fact, he is the Chief or Lord Buddha of Pure Land of Bliss within Heaven’s eastern quarter of Heaven. His name “Yakushi”, literally means “Medicine Professor”.
Yakushi made 12 resolutions or vows and the 7th vow is the resolution to disperse the illnesses of persons that called upon Yakushi’s name. “When my name is called for, all sick persons will be cured and their soul and body will instantly be tranquil and not have any sickly feeling”. Yakushi is assisted by two faithful attendants, Gakko and Nikko, and he also commands 12 divine generals, the Juni Shinsho, that are representing his 12 great vows.
Often, he is portrayed while carrying a medicine pot in one hand from which he is dispensing his healing medicines. His medicines are healing both body sickness and mental sickness. Yakushi Nyorai has never been depicted in the Garbhadhatu (Taizo-kai) Mandara nor the Vajaradhatu (Kongo-kai) Mandara.
In many Tibetan images, Yakushi is beautifully depicted in his personal Mandala, aptly named “The Medicine Buddha Mandala.” The Mandala itself has many layers of esoteric meaning which unfold as one moves forward on the healing path of the bodhisattva; in conjunction with appropriate guidance, teachings, and practices.
Senju Kannon Bosatsu (Avalokitesvara of a Thousand Hands)
Senju Kannon is probably the most popular portrayal, out of the many Avalokitesvara / Kannon grouping of deities in Esoteric Buddhism. The image is of feminine nature with a thousand arms, which hold many symbols/tools/mudras. Senju Kannon has a strong affinity with us and vice-versa, due to the suffering we endure and her continuous work for our salvation and relief.
The original name of this deity is Sahasrabhujasranetra or Senju-sengen Kannon which means the One Who has a Thousand Hand and Eyes. It is believed that this work is done via the various symbols/tools/mudras held in her hands. In some of the hands, one may observe an eye. It should be noted that in the uppermost hands she carries effigies of the sun and the moon.
Senju Kannon may also appear in alignment with Amitabha Tathagata, residing in the Western Pure Land. It is said that if you recite her mantra you clean your mind, to then enhance your innate Buddhahood and manifest your undefiled nature.
Kokuzo Bosatsu (Äkäsagarbha)
This bodhisattva represents the concepts of infinite merit and the infinite void. It is believed that praying to this bodhisattva will increase one’s memory. He is also believed to grant wisdom. Kokuzo Bosatsu was one of the first deities to he represented in sculpture in Japan, (this image, of course, is of a later date). The hand gestures (mudra) are the opposite of the Great Buddha. The right hand symbolizes the desire to end suffering, and the left hand welcomes those who suffer.
In its ultimate form, reality, and totality, the universe is called Mahavairocana or Dainichi Nyorai. Mahavairocana stands for “The Great Shining One” and this translates as Dainichi Nyorai in Japanese which means “The Great Sun Buddha”. This Dainichi Nyorai is in the literally sense everywhere and it is also everything!
All other Buddha’s (as well as Bodhisattvas) are actually aspects or emanations of Dainichi. There are many Buddha’s and Bodhisattvas and they all hold distinct but yet overlapping energy fields that refer to Dainichi’s love, wisdom, compassion, and some other activities. If you are worshipping or revering a specific Buddha, you’re worshipping Dainichi. When you’re revering and/or worshipping Dainichi, you simultaneously worship any of his Bodhisattvas or Buddha’s.
The central and key figure in Taizo-kai (Gharbadhatu) Mandaras (or Mandalas) and the Kongo-kai (Vajradhatu) is Dainichi Nyorai. In Japanese, the two distinct elements of Dainichi’s existence (his Teachings and Understanding them) are called “Ri” (for principle/reason) and “Chi” (for wisdom). Buddhist followers wanting to manifest their full Buddha understanding and potential are required to possess and master both elements to perfection.
You may look upon these elements as “Static Wisdom and the “Active Application” of that wisdom. If Wisdom wants to be truly vibrant and alive, it needs to have Application. Wisdom remains useless without Application, regardless of the best-intentioned energy. Thus, both of these elements of the Absolute (Understanding and the Application) need to be included in people’s lives if they ever want to achieve something of value in their lives.
In the Buddhist World, you’ll find no definition of what “Mastery” entails but Mastery will be instantly recognized. It may come in many varieties and shapes or forms but it always will follow unchanging specific laws. Mastery will lead to rewards, yet it is not a goal destination in itself. It is a process, a journey. The journey is “Mastery”.