仁王經疏 3.101

3.101

問：〈護國品〉言一日說八千億偈竟，如何一日能說如是八千億偈？解云：如來神力冥加被故。如《報恩經》，阿難暫時領得如來二十年中所說諸經，此亦如是。諸王聞佛所說十萬億偈，生歡喜故，散華供養。散華供養，即〈散華品〉。准此經文，此經一部自有廣略二本，如上應知。

Question: The "Chapter on Protecting the State" says that in one day eight thousand billion verses were spoken completely; how could so many eight thousand billion verses be spoken in a single day?
Answer: Because the Tathāgata's divine power secretly supported them. Just as in the Sūtra on Repaying Kindness, Ānanda momentarily received and comprehended the various sūtras spoken by the Tathāgata over twenty years, this is also likewise.
The various kings, having heard the hundred billion verses spoken by the Buddha, gave rise to joy and therefore scattered flowers in offering. Scattering flowers in offering constitutes the "Chapter on Scattering Flowers."
In accordance with this sūtra text, this single scripture inherently has two versions, an extensive and an abridged one, as should be understood as above.