This dissertation, "The Development of Religious Aspiration as Reflected in the Yogācāra-masters' Spiritual Practices in the *Abhidharma-Mahāvibhāṣā and in the Bodhisattva's Practices in the Basic Section in the Yogācārabhūmi" by Xianda, 贤达, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: This study is an attempt from a new angle to prove that Mahāyāna Schools emerged within the Buddhist monastic order itself rather than from some adventitious origins. My investigation focuses on the pre-Mahāyānic Śrāvaka-yāna's religious aspiration as reflected in the Sarvāstivādin yogācāra-masters' spiritual practices, and on the development of Bodhisattva-yāna's religious aspiration from MVŚ to the Basic Section of YBŚ. The thesis begins with a full survey on the yogācāra-masters within the broad Sarvāstivāda lineage, especially their doctrinal views and spiritual practices, which aims to exposit their interesting synthesis of Śrāvaka stance with Bodhisattva-like inclination, as shown in Chapter II. This is followed by scrutinizing the limitations and the imperfections of Arhats' spiritual attainments, especially in terms of non-defiled ignorance and residual traces, in contrast to the Buddha's attainments, as reflected in the literary sources of the Sarvāstivāda and Mahāyāna Yogācāra Schools. It shows that before the emergence of Mahāyāna, the Śrāvaka-yāna itself already well-understood the Arhat's inability to live up to the increasing expectation and to cater for the need of its followers, especially in providing spiritual guidance to salvage sentient beings to cross over the saṃsāric ocean like the Buddha did in the past. In the subsequent chapter, I document a process of defining "true Bodhisattva" in terms of Bodhicitta, and formulating the feasible soteriological path for the purpose of fulfilling the Bodhisattva's religious aspiration, as exemplified by the incorporation of five Mahāyānic thoughts into traditional practice of ten skillful action-paths for the cultivation of the karma for thirty-two marks of a great man in MVŚ. And in the fifth chapter, I also demonstrate a gradual process of articulation on the doctrine of Great Compassion according to the Abhidharmic method of analysis in MVŚ and formulation of Bodhisattva-yāna's practices in alignment with the doctrine of Great Compassion in YBŚ. This study shows that because of the presence of non-defiled ignorance and residual traces and without Great Compassion, which come down to be understood as the inability to guide sentient beings to cross over the saṃsāric ocean of death and rebirth, the Śrāvaka-yāna was considered not essentially different from the Pratyekabuddha-yāna, and the significance of its existence for Buddhist followers and for the continuous existence of Buddhism as a whole was also not more important than the Pratyekabuddha-yāna's. The need for a new Bodhisattva-yāna which could teach like the Buddha was well-recognized by the followers in different Śrāvaka groups during the time of MVŚ's compilation. This explains why the Sarvāstivādins and others were directly engaged in the formulation of Bodhisattva-yāna's doctrines, and why a cluster of Buddhists, if not all of them, during the period starting from the 1st century BCE to the 2nd century CE, embraced new religious aspiration for the attainment of Buddha-hood, which was previously believed to be unachievable. This seems to be also the most important reason for the Śrāvaka-yāna's fading away from the central stage of subsequent Buddhist history, and