Basic Meaning
In the Śrīmālādevī Siṃhanāda Sūtra it is explained that the dharmakāya of a buddha possesses the four perfect qualities of purity, bliss, permanence, and self.
See page 337: In Sanskrit, “the perfection of qualities,” referring to the four salutary qualities of the tathāgatagarbha: permanence, purity, bliss, and self, as described in the Śrīmālādevīsiṃhanādasūtra . These qualities are in distinction to the four perverted views (viparyāsa), where ignorant sentient beings regard the conditioned realm of saṃsāra as being permanent, pure, blissful, and self when in fact it is impermanent (anitya), impure (aśubha), suffering (duḥkha ), and not-self (anātman).
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