The Noble Mahāyāna Sūtra on the Four Factors

While residing in the Jeta Grove in Śrāvastī, the Buddha explains to an assembly of monks and bodhisattvas four factors of the path that bodhisattvas must not abandon even at the cost of their lives: (1) the thought of awakening, (2) the spiritual friend, (3) tolerance and lenience (which are here counted as one), and (4) dwelling in the wilderness. The sūtra concludes with two verses in which the Buddha restates the four factors and asserts that those who do not relinquish them will attain complete awakening.