四分律行事鈔資持記 3.796

3.796

《智論》，初段。六齋緣起，異上《智論》，蓋所出不同。先雖奉齋，盡日不食，復無善法；佛因誘接，故為加改。

In the Mahāprajñāpāramitopadeśa, the first passage on the origin of the six fast days differs from the Mahāprajñāpāramitopadeśa cited above, likely because they come from different places. Formerly, although they observed the fast by not eating for the whole day, there was no good dharma; because the Buddha was guiding and receiving them, he augmented and modified it.