Chūagon-kyō (Mādhyamāgama), Vol.9
This is one of the sutra scrolls which are sometimes called Zenkō Shuin-kyō (sutra with the red seal of Zenkō) since a seal with the name Zenkō is stamped in red onto the end segment of the scroll. There are about thirty extant scrolls of Zenkō Shuin-kyō sutras in Japan, and it is notable that the date of reference, the date of copying, the names of the copyist and the proof-reader, the type of the scroll mounting and pages are all written onto the end section of each scroll.
There are many unknown aspects about the Zenkō Shuin-kyō sutra. The nun Zenkō, who was the head of Hokke-ji temple, began the project of copying the Issai-kyō sutra collection in 755. The project is known to have continued until December 759, when it was still incomplete, but it is unknown what has become of the project thereafter. It is conceivable that the scroll introduced in this article belongs to the set of Issai-kyō sutras that were copied as a result of the Zenkō project. It was copied by Ichinan Hōrō, who was working at the studio for sutra copying on September 27, 759. The outstanding calligraphy of this sutra is notable. It is well known as one of the most excellent masterpieces among the copied sutras of the Nara period.
Masterpieces of Nara National Museum. Nara National Museum, 1993, pp.78-79, no.58.