佛祖統紀 33.39

33.39

述曰。目連託救母以興緣。如來示奉盆以垂法。所以教人道以報重恩也。自大教東流。古今帝王所以奉盆供者為多矣（事見會要志）然今之寺舍。多於此日施斛供亡。如常法者。雖無奉盆之儀。而不失盂蘭之意。

I comment: Maudgalyāyana relied on saving his mother to give rise to the occasion, and the Tathāgata demonstrated the offering of the bowl to bequeath the model; this was to teach people the way to repay weighty kindness. Since the Great Teaching flowed east, emperors and kings of past and present who have made the bowl offering have been numerous (the matters appear in the Treatise on Essential Compendia). However, nowadays monasteries mostly distribute bushel offerings for the deceased on this day in accordance with the ordinary ritual; although they lack the ceremony of offering the bowl, they do not lose the intent of the Ullambana.