Traditional Chan Buddhism is grounded in the principle of 'faith.' Whether it be the Chan methods of Bodhidharma's 'two entrances and four practices' or the various schools of Chan spanning from the Northern to Southern traditions, including the subsequent Linji lineage, practitioners are required to steadfastly adhere to a profound belief in Buddhist doctrines, transcending the cycle of life and death to attain Nirvana. Dahuai Zonggao, however, places 'doubt' at the core of his teachings. He advocates cultivating a questioning attitude towards the existential nature of life and death throughout the entire process of Chan meditation, directing this doubt toward the discourse, ultimately dismantling it at the point of discourse. The shift in Chan Buddhist thought from 'faith' to 'doubt' is not only intertwined with the personal experiences of Dahuai Zonggao but also represents an internal evolution within the Chan tradition. It emerges as an inevitable trajectory following the intersection of Confucian and Buddhist thought.