Page "Atiśa" Paragraph 15

According to Tibetan sources, Atiśa was ordained into the Mahasamghika lineage at the age of twenty-eight by the Abbot Śīlarakṣita and studied almost all Buddhist and non-Buddhist schools of his time, including teachings from Vishnu, Shiva, Tantric Hinduism and other beliefs.

He also studied the sixty-four kinds of art, the art of music and the art of logic and accomplished these studies until the age of twenty-two.

Among the many Buddhist lineages he studied, practiced and transmitted the three main lineages were the Lineage of the Profound Action transmitted by Maitreya / Asaṅga, Vasubandhu, the Lineage of Profound View transmitted by Manjushri / Nagarjuna, Chandrakirti, and the Lineage of Profound Experience transmitted by Vajradhara / Tilopa, Naropa.

It is said that Atiśa had more than 150 teachers, but one prominent teacher above all else was Dharmakīrti from Sumatra, Indonesia.