This was the golden age not only of Japanese Buddhism but also of Buddhist sculpture in Japan. Buddhism enjoyed a still greater measure of State protection than in the preceding period, and a new continental culture, that of the T'ang Dynasty, poured into the country. The State protection extended over Buddhism was shared in no small measure by Buddhist sculpture, so that works which required a great expenditure of money, or which had to be undertaken on a grand scale, were successfully accomplished, and the artists were allowed to show their genius and skill to the best possible advantage. The contemporary T'ang Empire of China (many of whose institutions were adopted by Japan) had been extending its dominion by the annexation of adjacent regions, and enriching its own culture by the absorption of the cultures of neighbouring states. Thanks to intimate intercourse with India, Persia and other countries of the Near East, the institutions of those Western lands were brought into China and much appreciated for their exotic appeal and fresh stimulus. What we must not overlook about them is their influence or effect on Japanese sculpture. In no other period of Japanese art-history was a richer variety of materials used by our sculptors, for new technical processes were introduced for the making of images of wood, metal, clay, lacquer, and stone, and each displays its special features to great account. The idealistic tendency of expression that had characterized the period preceding was modified in the Nara period by the realistic manner introduced from Western lands, which was ingeniously harmonized with the spiritual expression of the Far East to produce many masterpieces, thus bringing about what we have already described as the golden age of Japanese sculpture.

The importance of Buddhist sculpture cannot be overemphasized, since it forms the centre or core of Japanese sculpture. Because Buddhist images are cast or carved as objects of worship, they are, as such, subject to various rules and conventions, and some knowledge of these seems indispensable to the appreciation of Buddhist art.
A study of the probable motives that led to the birth and growth of Buddhist sculpture would seem to show that the art owes its origin and development to the tendency once strong in Buddhism to encourage the copying and reading of sutras and the making of sacred images as works of high religious merit. In all instances they were products of pious faith, and the attitude of the sculptors who brought them into being naturally had something different from that of ordinary artists. To begin with, Buddhist sculpture required (and still requires) the choice and use, as material, of wood or metal free from all taint of pollution, physical and moral. It also requires the artist himself to be pure in body and spirit. Finally while the work is in progress a series of religious rites must be performed for the further purification of both artist and image.
The form and features of a Buddhist image must conform to the scriptural description of the Buddha or other holy being it represents, and should not be altered at the discretion, much less at the caprice, of the artist. The rules and conventions regarding such matters were made more restrictive and exacting than ever in the eighth and ninth centuries, when the study of Buddhist iconography became more systematic than in all previous periods. Now, Buddhist images often have forms and features that may strike you as strange and unreal, if not, indeed, as unearthly, but these are all faithful embodiments of ideas and descriptions found in the sutras—supernatural beings and incarnations of virtue. Thus an image having a number of faces on its head is an attempt to symbolize a many-sided personality or nature (not a multiple personality in the bad sense), while a many-handed figure expresses versatility, each hand holding or showing some symbol of a special power, talent or ability. Highly specialized as are the symbolic forms and features of Buddhist images, they may be roughly classified into the four categorical types of Buddha images, Bodhisattva images, Fury images and Deva images.

Buddha Images Nyorai-gyō.

Images of this type represent those who have attained the highest degree of enlightenment in Buddhism. Their forms and features are modelled on those of Sakyamuni Buddha, founder of Buddhism, as attired in plain garments after he left home and family to seek complete emancipation from the ills of worldly life. He was great not merely in his spiritual attainments but is believed to have been unlike the generality of men in his physical features. Buddhist sutras attribute to him thirty-two or eighty special marks of Buddhahood. To mention the more important of them, he had an upright and graceful form, with a dignified bearing, ample shoulders and armpits and thighs, long and gentle fingers, feet with ample flesh and soles with circular marks, a filmy network between fingers and toes, soft and smooth skin with a golden lustre, long white scintillating hairs in his eyebrows and eyelashes, and a fleshy outgrowth on the top of his head.
Figures of other Buddhas or Tathagatas Nyorai are made more or less in imitation of the typical image of Sak-yamuni Buddha as outlined above, the difference amongst the Buddhas being shown mainly by the different shapes of their hands.

Bodhisattva Images Bosatu-gyō.

On the ground that a Bodhisattva is one who has not yet attained the full state of Buddhahood, he is represented in sculpture as having the form and features of Sakyamuni Buddha while he was still a royal prince by the name of Siddhartha Gautama. Buddhist images of the Bodhisattva type, therefore, have their hair done up in ample knots or coils, and adorn their person richly with head-coverings, ear-rings, necklaces, bracelets, and so forth. Many different Bodhisattvas are represented by images of this type, each recognizable by the shape of his hands or by what he holds in them and so forth.

Fury Images Hunnu-gyō.

Deva Images Tenbu-gyō.

Images of this type represent noble celestial beings who act as guardians of various virtues attributed to Buddhas and Bodhisattvas. They are as varied in form and features as in types of divine personality or function. They may, however, be roughly classified into those in martial attire and those in the form of persons of exalted station. Both are represented as closely resembling in form actual human beings of flesh and blood, and consequently allow the sculptor a good deal of latitude in variety and freedom of expression. This type of Buddhist sculpture thus offers him the most fertile field of imaginative work as to choice of theme and creative expression, with the result that we have a considerable number of superior works of art among our deva images.

Such, then, is the general classification, the validity of which is not affected by the few exceptions which certainly exist. It was natural that their modes of expression should have changed gradually so as to mirror the changing currents of religious thought and sentiment during the successive centuries.

A belief in kami or gods of Sintoism has existed in Japan from the oldest period of the nation's history. It has survived the introduction and spread of Buddhism, and continues its existence today. Images of Sinto deities, however, are by no means as numerous as the long history of the faith and its firm hold on the mind and heart of the race might lead one to expect. This is explained by the fact that in Old Japan all natural objects and phenomena which impressed one as divine or sacred were instinctively deified, so that no keen need was felt for the making of idols in human form as objects of adoration. Indeed, Sinto images began to be produced only about the ninth century, when there arose a compromise theory to the effect that Japanese gods and Indian Buddhas were identical in essence, a theory which helped or enabled the two religions to flourish together in harmony. There can thus be no shadow of doubt as to the paramount influence of Buddhist sculpture on Sinto images. In fact, some of those worshipped as Sinto deities were really Buddhist images used as substitutes! But there were others which were intended from the first as figures of native Sinto gods, and had characteristic forms and features as such. Most of these are figures of men and women clad in the native costumes of ancient Japan, and generally reveal a rather simple technique. They form a striking contrast to Buddhist images, with their Indian costumes and elaborate workmanship. The contrast was probably intentional, but we must also remember that Sinto images were always kept hidden in the holy of holies with their doors shut tight, unlike Buddhist figures, which are with only a few special exceptions exposed to view to delight the eyes of the worshippers and fill their souls with pious rapture. These circumstances explain why Sinto sculpture has not made progress comparable to that of the Buddhist art.