Qingyuan Xingsi (青原行思 - Qingyuan Xingsi, posthumously honored by Tang Emperor Xizong as Hongji Chanshi - 弘濟禪師, rendered in Sanskrit as महाप्रभावध्यानगुरु - Mahāprabhāvadhyānaguru, and in Tibetan as རྒྱ་ཆེན་ཕན་མཛད་བསམ་གཏན་སློབ་དཔོན། rgya chen phan mdzad bsam gtan slob dpon Gyachen Pendze Samten Lopön, universally revered across China, Japan, Korea, Vietnam, Taiwan, Hong Kong, and the global Buddhist world as one of the two supreme Dharma heirs of the Sixth Patriarch Huineng alongside Nanyue Huairang), acclaimed throughout Tang dynasty Buddhist history during the 7th century and 8th century as the ancestral patriarch of the Caodong (Soto), Yunmen, and Fayan houses of Chan, stands as a foundational pillar of Southern Chan Buddhism. With his year of birth in 660 and his year of death in 740, Qingyuan Xingsi was born with the secular surname Liu in Ancheng (modern Anfu County, Ji'an, Jiangxi Province) in southeastern China. Recognizing the pervasive reality of anicca and dukkha from early youth, he practiced fearless renunciation in childhood, took formal refuge in the Buddha, the Dharma, and the Sangha, entered the monastic order, and received full bhikshu ordination in the Vinaya Pitaka lineage while upholding strict monastic precepts and ethical conduct.

Initially practicing solitary contemplation and silent meditation, mindfulness, and concentration in his native Jiangxi Province, Qingyuan Xingsi rarely spoke in public assembly, preferring deep inward stillness until hearing of the extraordinary teaching of the Sixth Patriarch Huineng (638–713) at Nanhua Monastery at Caoxi in Guangdong Province. Journeying southward to Caoxi, Qingyuan Xingsi stood before Huineng and asked, “What must one do so as not to fall into gradations or stages?”—to which Huineng countered, “What have you been doing?” When Qingyuan Xingsi replied that he did not even practice the Four Noble Truths, Huineng asked what stage he fell into, and Qingyuan Xingsi famously answered, “If one does not even practice the Four Noble Truths, what stages could possibly exist?” Immediately recognizing Qingyuan Xingsi's profound realization of non-dual emptiness, Huineng praised him as a rare vessel of the Dharma and appointed him as the head monk and senior preceptor of the Caoxi assembly.

When Huineng entered final parinirvana in 713, he entrusted Qingyuan Xingsi with guiding the younger disciples, famously directing Shitou Xiqian (700–790) to seek instruction from Qingyuan Xingsi. Returning to his native Jiangxi Province, Qingyuan Xingsi settled at Jingju Monastery on Mount Qingyuan in Ji'an, where he taught quietly for nearly three decades, cultivating a contemplative community renowned for uncontrived simplicity, silent introspection, and direct experiential awakening.

At Mount Qingyuan, Qingyuan Xingsi transmitted the mind-seal to his foremost Dharma heir Shitou Xiqian—author of the celebrated Cantongqi (Harmony of Difference and Sameness)—famously testing Shitou Xiqian's realization by asking where he had come from and sending him on a symbolic errand to Nanyue Huairang (677–744), thereby demonstrating the complete non-sectarian unity between the Mount Qingyuan and Mount Heng lineages of Chan.

Through Shitou Xiqian and his successors Yaoshan Weiyan (745–828) and Tianhuang Daowu (748–807), Qingyuan Xingsi became the direct ancestral patriarch of three of the Five Houses of Chan—the Caodong (Soto) school founded by Dongshan Liangjie (807–869) and Caoshan Benji (840–901), the Yunmen school founded by Yunmen Wenyan (864–949), and the Fayan school founded by Fayan Wenyi (885–958)—carrying his contemplative lineage across China, Korea, Japan, and Vietnam.

Literarily, Qingyuan Xingsi's piercing enlightenment dialogues with Huineng and Shitou Xiqian are preserved across the foundational chronicles of the Chinese Tripitaka—including the Jingde Chuandeng Lu (Transmission of the Lamp, Taisho Number 2076 in the Chinese Tripitaka), the Zutang Ji (Patriarchs' Hall Collection), the Wudeng Huiyuan (Compendium of Five Lamps), and Huineng's Platform Sutra of the Sixth Patriarch (Taisho Number 2008)—alongside the core scriptures of his lineage such as the Vajracchedika Prajnaparamita Sutra (Diamond Sutra, Taisho Number 235, corresponding to Toh Number 16 in the Tibetan Tripitaka), the Lankavatara Sutra (Taisho Number 670, corresponding to Toh Number 107), and the Prajnaparamitahrdaya Sutra (Heart Sutra, Taisho Number 251, corresponding to Toh Number 21).

Philosophically and contemplatively, Qingyuan Xingsi embodied the non-gradual realization that innate Buddha-nature (tathagatagarbha) is completely whole and unstained right where one stands, transcending all artificial stages—harmonizing Nagarjuna's Madhyamaka dialectics regarding emptiness (शून्यता - śūnyatā; སྟོང་པ་ཉིད། stong pa nyid Tongpanyid) and dependent origination, Asanga and Vasubandhu's Yogacara insight into non-dual awareness, and Maitreya's Uttaratantra Shastra (Toh Number 4024, and Taisho Number 1611). Guiding practitioners to sever attachment to the five aggregates, anatta, emptiness of self, karma, and rebirth across samsara and nirvana, Qingyuan Xingsi anchored every moment of monastic life in Shakyamuni Buddha's Four Noble Truths, the Noble Eightfold Path, generosity, merit, loving-kindness, compassion, equanimity, right view, non-attachment, skillful means, and universal bodhicitta to extinguish the three poisons across the six realms.

Passing into final parinirvana at Jingju Monastery on Mount Qingyuan on December 13, 740 at the venerable age of eighty-one amidst deep veneration from his disciples and the entire Sangha, Qingyuan Xingsi left an immortal contemplative legacy that shaped the silent illumination and non-dual dialectics of East Asian Chan and Zen. Revered forever across China, Korea, Japan, and Vietnam as the great patriarch of Mount Qingyuan, Qingyuan Xingsi stands alongside Bodhidharma, Huineng, Nanyue Huairang, Shitou Xiqian, and Dongshan Liangjie as a supreme guardian of the Middle Way.