金剛般若波羅蜜經註解 1.266

1.266

有來、去、坐、臥者，乃如來應身也；無來、無去者，法身也。然如來昔行菩薩道時不受福報，云何至果有去、來、坐、臥之相，使諸眾生供養獲福？恐有此疑，故告以釋之，謂如來應用示有動作，而法身之體如如不動也。

Having coming, going, sitting, and lying down is the Tathāgata's nirmāṇakāya; having no coming and no going is the dharmakāya. Yet, when the Tathāgata previously practiced the bodhisattva path, he did not receive karmic rewards of merit; why, upon reaching the fruit, are there marks of going, coming, sitting, and lying down, causing all sentient beings to make offerings and obtain merit? Fearing there might be this doubt, he therefore spoke to resolve it, meaning that the Tathāgata's responsive application provisionally shows bodily activities, while the essence of the dharmakāya is such-like and unmoving.