Mahayana Uttaratantra Shastra - By Arya Maitreya
Arya Maitreya's Mahayana-Uttaratantra-Shastra is one of the most important teachings on Buddha-nature and enlightenment. It is revered by Buddhist masters as a very special text, one of the five great teachings given by Lord Maitreya to Asanga, and part of the third turning of the wheel of the Dharma.
Within the traditional Buddhist shedras for monastic education, it is often taught as the final text in the curriculum, and many masters say it can be considered a bridge between the sutras and tantra. It provides an important philosophical foundation for understanding the workings of the Buddhist path, particularly for Vajrayana practitioners.
The Uttara Tantra is one of the main texts of the Mahayana path. It establishes that there is Buddha-nature in all sentient beings. It is the presence of this essence which makes it possible for all sentient beings, without a single exception, to eventually achieve enlightenment.
This essence, however, does not simply manifest in ordinary beings because it is covered up by the defilements. The Uttara Tantra goes into detail showing what this essence is and how it is covered up. It also discusses the qualities of a person when all the obscurations are removed so the Uttara Tantra is also a guide to Buddhahood.
Because the understanding of Buddha-nature is essential for the understanding of the Mahayana path, this text is studied in monastic colleges of all sects in Tibet. However, the root text written by the Maitreya Buddha was written in an extremely terse and subtle language so that the Uttara Tantra is almost always accompanied by a commentary by a lama.