大般涅槃經義記 6.306

6.306

第五權時放捨喻中，如來告彼親化菩薩，彰己更欲遷化異境名「語瞻病」。吾今劇務，斯後化度名「當更來」。隨情所堪，授以世法，名「隨所須恣意勿遮」。捨之取滅名「即還家」。彼起微善感聖名曰「使到」，如來知其未堪受化即未從就，是以告使：「我事未訖，兼未合藥」，明己餘方為化未周名事未訖，佛未量機以授其法名未合藥。喻相難識，不可盡合；設有合者，未可專定。

In the fifth, the analogy of temporarily letting them go, the Tathāgata informs the bodhisattva who directly converts him, showing that he intends to move on to convert another realm, which is called "addressing the caretaker." "I am now exceedingly busy, and will convert and deliver him later" is called "I shall come again." In accordance with what his disposition can bear, he bestows conventional dharmas, which is called "give him whatever he needs at will, do not withhold it." Leaving him and entering extinction is called "promptly returning home." The person giving rise to faint good that moves the sage is called "the messenger arrives"; the Tathāgata knows that he is not yet capable of receiving conversion and therefore does not immediately follow, so he tells the messenger: "My tasks are not yet finished, and moreover I have not yet compounded the medicine"—explaining that his work of converting other regions is not yet complete is called "tasks not yet finished"; the Buddha having not yet weighed the capacity to bestow the Dharma on him is called "not yet compounded the medicine." The features of the analogy are difficult to discern and cannot be completely aligned; even if some are aligned, they cannot be definitively fixed.