The Mogao Cave 156 is constructed in honor of Zhang Yichao, the military commissioner of the Guiyi Circuit. Since the Guiyi Circuit led by Zhang started governing the Tibetan regime, it adopted the influence brought by the Tibetans. The layout of Mogao Cave 156 and 161, as well as the combination of a pagoda on top of these caves, are originated from the Tibetan pagoda-grotto combination. The cave was not only influenced by the pagoda-grotto combination in the Tibetan tradition, but it was also deliberately made to serve as a mandala of Buddhism practices and rituals. Cave 156 and some others make up to two caves and one pagoda, forming the “temple,” which is viewed as one mandala; the front chamber of cave 156 is the outer altar. When entering the outer altar, one will see the images of the Four Heavenly Kings; when walking along the aisle, one will be welcomed by the images of the cave owner, Zhang Yichao. The west niche of the main chamber is the inner altar. The top of the niche, connected with cave 161, is the Dharma essence of the inner altar, while the pagoda on top of the cave is the final state of the Dharma essence. As seen from the images and spaces, a visitor will be instructed by the Esoteric Buddhism practitioner inside the cave, using the Cundi mandala on the aisle ceiling and the Thousand-Arms Guanyin mandala at the top of the niche on the west wall as connection points to connect to the upper floors of Cave 161. From Cave 161, which is filled with drawn images of Bodhisattva, it extends to the pagoda filled with many images of Bodhisattva. It is in this way that the practices and rituals of Esoteric Buddhism unfolded, within a temple space comprised of two caves and pagoda.
