成唯識論掌中樞要 2.269

2.269

大涅槃體有二義：一、理三事，即於真如有摩訶般若、解脫、法身三義故；二、體三事，三體各別故，合名「大涅槃」。

The essence of the great nirvāṇa has two meanings: first, the three aspects in principle, namely that within suchness there are the three meanings of mahā-prajñā, liberation, and dharma-kāya; second, the three aspects in substantial entity, because the three entities are each distinct, together called 'great nirvāṇa'.