The Pratyutpanna Sutra (also Pratyutpanna Samadhi Sutra, lit. "The Samadhi of being in the presence of all the Buddhas"/Simplified Chinese 佛说般舟三昧经 ) is an early Mahayana Buddhist scripture, which probably originated around the 1st century BCE in the Gandhara area of northwestern India.
The Pratyutpanna Sutra was first translated into Chinese by the Kushan Buddhist monk Lokaksema between 178 and 189 CE, at the Han capital of Loyang. This translation is, together with the Prajnaparamita Sutra, one of the earliest historically datable texts of the Mahayana tradition.
The Pratyutpanna Sutra contains the first known mentions of the Buddha Amitabha and his Pure Land, said to be at the origin of Pure Land practice in China:
"Bodhisattvas hear about the Buddha Amitabha and call him to mind again and again in this land. Because of this calling to mind, they see the Buddha Amitabha. Having seen him they ask him what dharmas it takes to be born in the realm of the Buddha Amitabha. Then the Buddha Amitabha says to these bodhisattvas: 'If you wish to come and be born in my realm, you must always call me to mind again and again, you must always keep this thought in mind without letting up, and thus you will succeed in coming to be born in my realm." Pratyutpanna Samadhi Sutra, translated by Jeff Wilson.
The full practice developed by Zhiyi is 90 days long. Lay practitioners often take a much shorter time. Any practice that exceeds one day requires a bystander called a dharma protector (護法) to look after the practitioner. The exercise includes constant walking or praying to Amitabha, sometimes accompanying or helped by the bystander. The practitioner should avoid sitting, laying, resting or sleeping during the period of practice. The bystander would warn the practitioner if he or she engages in prolonged resting. Very few Buddhists practice this. Yinkuang (印光) suggested that people should practice the much easier recitation of name of the Buddha nianfo instead. But some buddhists have said that they feel healthier after the practice.