法華義疏 2.217

2.217

經中或但明內外施攝一切施，或明三施，一內、二外、三亦內外。內外者如菩薩吐其所食施與餓鬼。

Sūtras sometimes explain internal and external giving as subsuming all giving, or explain three kinds of giving: first, internal; second, external; third, both internal and external. "Both internal and external" is like a bodhisattva vomiting up the food he has eaten to give it to hungry ghosts.