Buddhism
Jōdo Shinshū ("True Pure Land School"), also known as Shin or Shin-shu Buddhism, is a branch of Pure Land Buddhism which was founded in Japan by the monk Shinran (1173-1262) and organized by Rennyo (1414-99). It is a lay movement with no monks or monasteries and is based on simple but absolute devotion to Amida. In Shin-shu, the nembutsu is an act of gratitude, not one of supplication or trust.
Shinran's thought was influenced by an understanding of mappō, or the decline of the Dharma. Shinran saw the age he was living in as being in a degenerate age where beings cannot hope to be able to extricate themselves from the cycle of birth and death through their own power, or jiriki. For Shinran, all conscious efforts towards achieving enlightenment and realizing the Bodhisattva ideal were contrived and rooted in selfish ignorance; inauthentic in nature, for humans of this age and beyond are so deeply rooted in karmic evil as to be incapable not only of attainment but also of the truly altruistic compassion that is requisite in becoming a Bodhisattva. Thus, Shinran advocates tariki, or reliance on Other Power - the power of Amida Buddha's limitless and infinite compassion made manifest in the Primal Vow - in order to attain liberation.
Shin Buddhism can be understood as a "practiceless practice," for there are no specific acts to be performed. Jōdo Shinshū divided into two factions in the 17th century: Otani and Honganji. Both have their main temples in Kyoto, Japan and both remain powerful in Japan. itself has many sub-sects. In the United States, the Nishi-Hongwanji subsect operates as the Buddhist Churches of America.
Reference: http://www.religionfacts.com/buddhism/sects/pure_land.htm