This dissertation is an ethnohistorical study of an Afghan branch of the Naqshbandiyya/Mujaddidiyya order, the Saifiyya. The problem this study addresses is how the Saifiyya order is able to sustain and perpetuate itself over time. Recent historical studies attribute the survival of the orders to official patronage or an ability to adapt, in a variety of ways, to changes in the social and political environment. These analyses, however, stress mainly adaptation to social change. Few scholars have examined how social forces interact with spiritual practice such that the order remains the same in important respects. Because the reason for this oversight is chiefly methodological, this study uses broader methods, combining textual analysis with participatory field work. The Saifiyya identity is informed mainly by the renowned Naqshbandi religious reviver of the seventeenth century, Ahmad Sirhindi. Sirhindi preached the inseparability of shari'a and tarīqa and the continued validity of taqlīd or imitation of Islamic norms accumulated in the first ten centuries of Islam. Beginning in the eighteenth century, however, many spiritual heirs of the Naqshbandiyya rejected taqlīd, in order to address the social crises overtaking the Asian sub-continent. For some, reform eventually led to outright rejection of mysticism. In Afghanistan, government efforts to modernize prompted lineal Mujaddidiyya shaikhs to adopt political Islam, a strategy that similarly led to a loss of its mystical fimction. By contrast, the Saifiyya branch of the order continues to adhere to taqlīd. Until recently, the relatively stable society of northern Afghanistan was conducive to this approach, because it was somewhat removed from the social crises affecting the subcontinent and Afghanistan's urban areas. The result has been the preservation of a powerful baraka embodied in the order's shaikh, Saifur Rahman. Although forced to relocate to Pakistan, the Saifiyya order thrives, despite the presence of anti-mystical reform movements there. Saifiir Rahman attracts a growing number of disciples with the ecstatic and transforming power of his baraka. While the order's success is due partly to its ethnic and linguistic compatibility with the region, more than anything, it is the Pir's baraka that explains the order's growing social appeal today.