佛說盂蘭盆經疏 2.85

2.85

「善男子！若比丘比丘尼、國王太子大臣宰相三公百官、萬民庶人行慈孝者，皆應先為所生現在父母、過去七世父母，於七月十五日佛歡喜日僧自恣日，以百味飯食安盂蘭盆中，施十方自恣僧。」

"Good sons! If monks, nuns, kings, crown princes, grand ministers, prime ministers, the three dukes, the hundred officials, and the myriad common people who practice loving-kindness and filial piety would do so, they should all first, for the sake of the parents who gave birth to them in the present life and their past parents of seven lifetimes, on the fifteenth day of the seventh month—the day of the Buddha's joy, the day of the saṅgha's pravāraṇā—place foods and drinks of a hundred delicacies within an Ullambana basin and offer them to the pravāraṇā saṅgha of the ten directions."