大宋僧史略 2.26

2.26

首座之名即上座也。居席之端。處僧之上。故曰也。尋唐世勅辯章檢校修寺。宣宗賞其功署三教首座。元和中端甫止稱三教談論。蓋以帝王誕節。偶屬徵呼。登內殿而讚揚。對異宗而商搉。故標三教之字。未必該通六籍博綜二篇。通本教之諸科。控群賢而傑出而脫。或遍善他宗。原精我教對王臣而無畏。挫執滯而有功。膺于此名則無愧色矣。次後經論之學或置首座。三教首座則辯章為始也。朱梁洎周。或除或立。悉謂隨時。今大宋有講經講論首座。乃僧錄之外別立耳。

The name "Seat Head" (shouzuo) is precisely the sthavira (Seat Upper). He occupies the head of the assembly and sits above the monks; therefore it is so called. Investigating this: in the Tang dynasty, an imperial edict ordered Bianzhang to inspect and oversee the repair of a temple; Xuanzong rewarded his merits and appointed him Seat Head of the Three Teachings. During the Yuanhe reign period, Duanfu was only called "Discussant of the Three Teachings." This was because on imperial birthdays, one might happen to be summoned to ascend the inner palace halls to deliver praises and engage in disputations with other traditions; thus the label "Three Teachings" was marked. He did not necessarily have to master the Six Classics or broadly synthesize the two treatises; [rather, he had to] master all the branches of our own teaching, rising above and standing out among all the worthy scholars. But if he happened to be thoroughly versed in other traditions while deeply mastering our own teaching, facing kings and ministers without fear, and achieving merit by subduing stubborn attachments, he would bear this title with no sense of shame. Later, seat heads were sometimes established for the study of the sūtras and treatises, but Bianzhang was the first Seat Head of the Three Teachings. From the Later Liang down to the Zhou, the post was sometimes abolished and sometimes instituted, all according to the needs of the times. Today under our Great Song, there are Seat Heads for Lecturing on Sūtras and Seat Heads for Lecturing on Treatises; these are simply established separately outside of the Buddhist Registrars.