Traditionally there have been various views put forth concerning the sūtra upon which Vasubandhu’s Jingtu lun is a commentary, yet there is no established theory. Susumu Ōtake pointed out many passages within the Larger and Smaller Sukhāvatīvyūha sūtras used as scriptural sources for the Verses of Aspiration for Birth in the Pure Land （VABP）, and he concluded that both sūtras are the target of the commentary.
Regarding Ōtake’s theory, I proposed the Larger Sukhāvatīvyūha as a Single Sūtra Theory in my 2022 article. The basis for that is the following three points. First, without relying on the Smaller Sukhāvatīvyūha, with the Larger Sukhāvatīvyūha as a single sūtra source, Vasubandhu could have composed VABP. Second, among the other works of Vasubandhu which are titled “upadeśa,” all are commentaries on a single sūtra. Third, although it is certain that Vasubandhu knew the Smaller Sukhāvatīvyūha, that is not a definitive reason to include that as a basis for his commentary. This paper points out multiple scriptural sources for VABP from the multiple versions of the Larger Sukhāvatīvyūha which have not been cited by Ōtake, in order to support the first point given above.
