This short commentary, ascribed to Vasubandhu, explains The Noble Mahāyāna Sūtra on the Four Factors (Ārya­catur­dharmaka­nāma­mahāyāna­sūtra, Toh 251), a discourse on a set of four factors of the path of a bodhisattva: the thought of awakening, the spiritual friend, the twin qualities of tolerance and lenience, and dwelling in the forest. The commentary proposes various reasons for the sūtra’s composition and explains why it refers to bodhisattvas as followers of the Great Vehicle. It also specifies the four factors, which obstructive elements these factors overcome, which beneficial elements they support, and why śrāvakas and pratyekabuddhas are not called bodhisattvas.