佛頂尊勝陀羅尼經教跡義記 2.44

2.44

唐云甘露灌頂，亦稱云不死句。不死句者，解脫法身也。解曰：藥中最上者無過甘露，著毒之者服乃必除。闡提不信，謗法尤深，灌頂加持定當不死，以真言甘露塵累清淨，執遣界空名為解脫，離縛得脫即顯法身，悲智雙修名不死句也。又解：天降甘雨草木生芽，灌頂潤身亦成證也。

In Chinese it means "amṛta consecration," and is also called the "deathless phrase." The deathless phrase is the liberated dharmakāya. Explanation: Among medicines, the supreme has nothing exceeding amṛta; those affected by poison will certainly have it eliminated upon ingesting it. Icchantikas do not believe and slander the Dharma most deeply; by consecration and empowerment, they are certain to attain the deathless. Because the dust and defilements are purified by the amṛta of the mantra, grasping is dispelled and the realms are emptied, which is called liberation; being freed from bondage and attaining release reveals the dharmakāya; cultivating both compassion and wisdom is called the deathless phrase. Another explanation: When heaven sends down sweet rain, the grasses and trees sprout; consecration moistening the body also brings about realization.