大乘法苑義林章 7.6

7.6

第三開合廢立者，諸經論中或總名一佛寶，覺性、覺相、覺用三種同覺滿故，合名為佛。《涅槃經》等唯說三寶真體同故，說一法身。

Third, regarding differentiation and combination, dismissal and establishment: in various sūtras and treatises, they are sometimes collectively called the single Buddha-jewel, because the three kinds—the awakened nature, the awakened marks, and the awakened function—equally fulfill awakening, and so are combined and named 'Buddha'. The *Nirvāṇa-sūtra* and others speak only of one dharmakāya, because the true essence of the three jewels is identical.