The information from Tunhuang manuscripts of S.0735 "Non-Arising Expedient Means Gate of Mahayana Buddhism" and S.2595 "Concept of 'Observing the Mind'" indicates that Shen Hsiu of Northern School of Zen Buddhism once carried out the practice of Zen action of kṣama for absolution from sin in Doctrine of the Bodhisattva Sadhana. His practice of kṣama embraces the Zen meditative contemplation of purity of "No rise of thoughts in the mind of support," the doctrine of purity mind possessed by the public, as it is one Zen action of revelation and practice and mutual illumination and benefits for Doctrine of the Bodhisattva, kṣama for absolution from sin and Zen meditative contemplation of purity. According to the information from P.2911 "Seven Etiquettes of Hsiu Zen Master," Shen Hsiu of School of Zen Buddhism also values the combination of Sadhana of kṣama rituals and Zen Meditative Contemplation of purity. Notwithstanding, the practice goes beyond the general kṣama rituals which discloses the immeasurable boundless nigha (sin), as it also emphasizes the kṣama practice of "Internally Clear Mind," "Overturn Mind to Do Virtuous Deeds," and "Tathata Nirvana" that demonstrates the distinguishing feature of Zen Buddhism of Shen Hsiu.
