relationship among these topics is explained in RGV I.3:From the Buddha [comes] the dharma and from the dharma, the noble saṃgha. Within the saṃgha, the [tathāgata] heart leads to the attainment of wisdom. The attainment of that wisdom is the supreme awakening that is endowed with the attributes such as the powers that promote the welfare of all sentient beings. (RGV I.3) Buddha-nature The Ratnagotravibhāga is notable for its exploration of the doctrine of the buddhadhātu ("buddha nature", "buddha source" or "buddha essence", Chinese: 佛性, pinyin: fóxìng), also called buddhagarbha, jinagarbha and tathāgatagarbha (Wylie: 'de bzhin gshegs pa'i snying po; Chinese: 如来藏 rúláizàng). According to the RGV, all sentient beings have this permanent Buddha element within even though it is covered over by defilements (which are fully absent in a buddha). The buddha-nature is the common element shared by sentient beings, bodhisattvas and buddhas and as the RGV states "all corporeal beings are said to contain a Buddha" (Sanskrit: sarve dehino buddhagarbhāḥ). The RGV verses describe buddha nature as follows:Always, by nature, unafflicted; like a clear jewel, the sky, or water; it follows from faith in the dharma, superior insight, concentration and compassion (30); [its] results are the perfected qualities of purity, selfhood, bliss, and permanence, with the functions that are aversion to suffering and the appetite and aspiration for the achievement of peace (35); like the ocean, being an inexhaustible store of treasured qualities, and like a lamp, being naturally conjoined with qualities that are inseparable from it (42). What is taught by those who perceive reality is the distinction between ordinary persons, noble persons and Buddhas in terms of reality (tathatā): hence is it taught that this womb/chamber for a victor exists in sentient beings (sattveṣu jinagarbho ’yaṃ) (45); [depending on whether this reality is] impure, impure yet pure or perfectly pure, it refers to the realm of sentient beings, the bodhisattva or the Tathāgata [respectively] (47). (RGV 1.30, 35, 42, 45, 47).According to the RGV, this essence or basic element (dhātu) is always present in all beings and is the true essence of every living being and the source of all virtuous qualities, including Buddhahood. The RGV states:This [dhātu] is of unchanging character, due to its conjunction with inexhaustible qualities; it is the refuge of the world, due to it having no limit ahead of it; it is always non-dual, due to being without discrimination; it is