The Mahayana Mahaparinirvana Sutra

This sutra is the study of what can be called "Nirvana Sutra Buddhism" or "Tathagatagarbha Buddhism". It is a very positive, balanced, faith-promoting and spiritually affirmative manifestation of Buddhism, which recognises the hidden reality of the unconditioned, egoless Buddha-Self in all beings. That Self of the Buddha is a mystery, beyond the reach and grasp of the samsaric intellect: while the Buddha-Self is real, it is certainly not comparable to our worldly, selfish self (ego) and cannot truly be captured within the net of words or concepts. Yet it is the only enduring Truth that can ever be found. This sutra leads us to the Ultimate Truth and indicate the Path to tread for an Awakening into Reality's presence, which is all-pervading and eternal. That eternally present Truth is the sole genuine Reality."You, monks, should not thus cultivate the notion of impermanence, suffering and non-Self, the notion of impurity and so forth, deeming them to be the true meaning of the Dharma, as those people searching in a pool for a radiant gem did, each thinking that bits of brick, stones, grass and gravel were the jewel. You should train yourselves well in efficacious means. In every situation, constantly meditate upon the idea of the Self, the idea of the Eternal, the Bliss, and the Pure ... Those who, desirous of attaining Reality, meditatatively cultivate these ideas, namely, the ideas of the Self, the Eternal, the Bliss, and the Pure, will skilfully bring forth the jewel, just like that wise person who obtained the genuine, priceless gem, rather than worthless detritus misperceived as the real thing."- The Buddha, Chapter Three, The Mahayana Mahaparinirvana Sutra