法華義疏 1.135

1.135

「佛」者，第四、標教主也。所以標佛者凡有五義：一者、阿難答迦葉問。迦葉問云：「佛在何處最初說法？」故標佛也。二者、若不標佛直明五事，則不知此經為是魔說、為是佛說？為內道說、為外道說？今欲別邪正內外，故標於佛。三者、佛法有五人說：一、佛說；二、弟子說；三、諸天說；四、仙人說；五、化人說。今欲明此經是佛所說，非餘人說，故標佛也。四者、以後代眾生聞是佛說則深起敬信，故標佛也。五者、為欲成經是故標佛。凡是佛說亦須標佛，弟子之說又須標佛，如《維摩》、《勝鬘》等經皆標於佛，若不標佛則不成經也。

"Buddha" is fourth, designating the master of the teaching. There are, in general, five reasons for designating the Buddha:
First, Ānanda answered Kāśyapa's question. Kāśyapa asked: "Where did the Buddha initially preach the Dharma?" Therefore the Buddha is designated.
Second, if the Buddha were not designated and the five matters were directly clarified, one would not know whether this sūtra was preached by Māra or preached by the Buddha, whether it was preached by an insider path or preached by an outsider path. Now, wishing to distinguish the correct from the false and the internal from the external, the Buddha is designated.
Third, the Buddhadharma is spoken by five kinds of persons: 1. spoken by the Buddha; 2. spoken by disciples; 3. spoken by the devas; 4. spoken by ṛṣis; 5. spoken by apparitional beings. Now, wishing to clarify that this sūtra was spoken by the Buddha and not by other persons, the Buddha is designated.
Fourth, so that sentient beings of later generations, hearing that it was spoken by the Buddha, will give rise to deep reverence and faith, the Buddha is designated.
Fifth, in order to constitute a sūtra, the Buddha is designated. Wherever it is spoken by the Buddha, the Buddha must be designated; where it is spoken by disciples, the Buddha must also be designated. Sūtras such as the *Vimalakīrti* and the *Śrīmālādevī* all designate the Buddha; if the Buddha were not designated, it would not constitute a sūtra.