法華玄論 2.105

2.105

答：後文舉因說果，明行菩薩道時所得壽命于今未盡，況得佛壽命而可盡耶？如在太子之位資財猶尚未竭，況登天子之位俸祿可盡耶？

Answer: The later passage brings up the cause to speak of the fruit, explaining that the lifespan attained when practicing the bodhisattva path has not even ended today—how much less could the lifespan attained as a Buddha come to an end? Just as when in the position of crown prince one's wealth has not yet been exhausted, how much less could the revenue be exhausted once one has ascended the position of the Son of Heaven?