Matrix of the Thus Come One Sutra ［如来蔵経］ ( Tathāgatagarbha-sūtra; Chin Ju-lai-tsang-ching; Nyoraizō-kyō): A sutra that sets forth the concept of the matrix of the Thus Come One, i.e., that each person is the matrix, womb, or embryo of a Thus Come One, or Buddha. This means that all persons possess the Buddha nature, that all people are potential Buddhas.
The Sanskrit text is generally thought to have been produced in the early third century, but is not extant. A Tibetan translation and two Chinese translations exist. Of the Chinese translations, Buddhabhadra (359–429) produced one, and Pu-k’ung ( Amoghavajra, 705–774), the other. The “matrix of the Thus Come One” became a core concept of Mahayana Buddhism, and this sutra is regarded as one of the earliest to address it. Around the fourth or fifth century, Vasubandhu and Sāramati delved into the concept in their respective treatises The Treatise on the Buddha Nature and The Treatise on the Treasure Vehicle of Buddhahood. The principle that “all living beings alike possess the Buddha nature,” which appears repeatedly in the Nirvana Sutra, and the Lotus Sutra’s teaching of the one Buddha vehicle are related to the concept of the matrix of the Thus Come One.