At the core of Esoteric Buddhism is the idea that one can attain Buddhahood during a single lifetime. To achieve this goal, practitioners meditate upon cosmic diagrams known as mandalas in conjunction with performing hand gestures (mudras) and voicing sacred formulas (mantras). Due to their potency and complexity, initiates must perform these exercises with the guidance of a teacher.
At the center of each of the two principal mandalas of Japanese Esoteric Buddhism is the Buddha Dainichi Nyorai (Mahavairochana), the embodiment of universal truth. All of the other figures and forms in the mandalas are emanations that spring forth from the Buddha. Some of the emanations take the form of many-headed or armed beings, others of geometric shapes, and still others of objects such as swords or jewels. Each and every one—from the beautiful to the fearsome, from the figural to the abstract—is an aspect of the Buddha, an element of the truth.
Unique to Japanese Esoteric Buddhism is the weaving of gods and goddesses of the indigenous Shinto tradition into the conception of the cosmos of the Buddha Dainichi. Shinto deities associated with Esoteric Buddhist sites are often presented as avatars of Dainichi—manifestations within the Shinto universe of the truth existing in the Buddhist cosmos. In this way, the Buddhist deities depicted in mandalas are mapped onto distinctly Japanese geographical sacred spaces.
Left: Mandala of Han'nya Bosatsu. Nanbokuchō period (1336–92), 14th century. Hanging scroll; ink, color, gold and gold foil on silk; image: 64 1/2 x 48 5/8 in. (163.8 x 123.5 cm). The Metropolitan Museum of Art, New York, Gift of the Mary and Jackson Burke Foundation, 2000 (2000.289)