佛祖統紀 43.50

43.50

三年。詔天下係帳童行並與剃度。自今後讀經及三百紙。所業精熟者。方許係帳○詔以御製三藏聖教序賜天息災等。令冠新譯經首。

In the third year, an imperial decree ordered that registered postulants throughout the realm all be tonsured. From this time forward, only those who had read three hundred sheets of sūtras and were thoroughly proficient in their studies were permitted to be registered. An imperial decree granted the imperial preface to the Tripiṭaka Holy Teachings to Tianxizai and the others, ordering that it be placed at the beginning of the newly translated sūtras.