This is one of over 30 relief small Buddha shrines called the Hokeiji Stone Images of Buddha. Hokeiji Temple was located near the South Gate (Einei Gate) of Changan Castle during the Ming period. At present, a brick pagoda remains. However, the inscriptions on some of the images of Buddha say that they were originally enshrined at Kotakuji Temple located south of Daimeikyu of Changan Castle and that they were created during the Changan era (703 – 704). Kotakuji Temple was built in commemoration of the discovery of Buddha's ashes at the site in 677. Empress Wu Zetian (690 – 705), the only empress in the history of China, built Shippodai here and the stone images of Buddha were created for the decoration of the pagoda.
This trinity comprises a sitting Tathagata image and two attendants standing on each side of the Tathagata image. From a comparison with other similar trinity images, it can be said that the central image of this trinity was Miroku Tathagata. The central image of other trinities includes Amitaba and Tathaba with a goma-in sign (a sign to expel evil). Among the Hokeiji Stone Images of Buddha, there are also single images of standing eleven-headed Kannon Bodhisattva.