The year one in the Islamic calendar (622 C.E.) is reckoned from Muhammad's emigration (hijra) northward from Mecca to Madina. When Muhammad left Mecca, he fled as an outcast because of his promotion of a single god and the recognition of an egalitarian community of believers. Such views threatened the urban fabric of his day; yet his version of monotheism gained followers rapidly.

Muhammad's triumphal return to Mecca established Islam as a religious force that was to transform the world in many ways. Today Muslims (literally, those who accept Islam) number more than one billion individuals representing a diversity of national heritages, cultural traditions, and political perspectives. All Muslims accept the notion of a single god, the God of Abra-ham, and a long line of prophets who preceded Muhammad (including, among others, Adam, Noah, Abraham, and Jesus). The principles of Islam are believed to have been received by the Prophet Muhammad in a series of revelations later codified in a book format known as the Qur’an (literally, recitations).

The Qur’an seemingly covers all aspects of how to conduct oneself as a Muslim. It continues to serve today, as it has throughout Islamic history, as the primary source for ethics, behavior, and legal decisions within Islamic communities. At the time of the death of Muhammad, however, it was dis-covered that there was no provision for his succession -- a lapse that resulted in the bifurcation of the burgeoning Islamic community that has persisted to the present. Sunni Muslims, representing the will of the majority, presumed leadership by election of equals within the community; Shi’i Muslims (literally, partisans of ‘Ali, who was the son-in-law of Muhammad) sought a more traditional succession determined by familial lineage. Shi’ites today are most often associated in the West with state authority in Iran. They comprise a small minority (140 million) in contrast to Sunni Muslims, who number nearly one billion individuals.

James Bill and John Alden Williams have taken upon them-selves the admirable but ambitious task of explaining Shi’ism to a Western non-specialist audience. Professors at the College of William and Mary in Williamsburg, Virginia, they are widely respected for their expertise in International Relations and Middle Eastern Studies, respectively. In Roman Catholics and Shi’i Muslims, they present a clearly written comparison of Shi’ism with Roman Catholicism in which many surprising parallels are brought to the fore. Although Roman Catholics outnumber Shi’ites by about 10:1, Bill and Williams observe that both faith systems are transnational and universalistic, both rely upon the intercession of saints and sacred actors (Jesus and Mary; Husayn and Fatima), both value redemptive suffering and martyrdom, the triumph of compassion and forgiveness over vindictiveness and cruelty. Roman Catholicism developed within the larger context of Christianity; Shi’i Islam evolved in relation to the historical development of Islam.

The comparative method advanced in this book serves a useful function in drawing attention to otherwise unrecognized similarities, which may lead to better cross-cultural under-standings. What is particularly interesting, however, is that these similarities are themselves not relational in a historical sense, a fact that broadens our horizons to the potential understanding of religion as a human phenomenon.

Shi’i Islam today is the majority religion in Iran, Iraq, Azerbaijan, and Bahrein, with sizeable minorities in Pakistan, Turkey, Kuwait, Lebanon, and Afghanistan. Sunni Muslims throughout the world accept four orthodox caliphs, or succes-sors to the Prophet Muhammad -- Abu Bakr, ‘Uthman, ‘Umar and ‘Ali. Shi’i Muslims accept ‘Ali as the first righteous caliph. While all Muslims accept the Islamic creed, "There is no god but God, and Muhammad is his prophet," Shi’i Muslims add to this the attestation, "‘Ali is the companion of God." Of the three major divisions of Shi’ism, Zaydi, Isma’ili, and Ithna’ashari, it is the third, or Twelver Shi’ism, that is the focus of this book. Shi’i Muslims were often subject to perse-cution in Sunni communities; in response to this, in the eighth century C.E., Ja’far, the sixth Imam (divinely ordained leader of the Shi’ite community) advocated taqqiya, or dissimulation of religious beliefs, which became an essential component of Shi’i doctrine. According to Shi’i belief, the twelfth Imam disap-peared and remains absent (ghayba), and will return at the end of time to an era of peace and justice in the world.

In contrast with Sunni Muslims, Shi’i Muslims believe that the final word has not been said, that the Qur’an is continually open to personal interpretation (ijtihad). They also believe that God has given his people choice (ikhtiyar), counter to notions of predestination. Like Catholics, Shi’i Muslims believe in saints and intercession, and they undertake pilgrimages to shrines and holy places for personal benefit. The role of redemptive suffering is central to both Catholics and Shi’i Muslims, but are not accepted in Sunni Islam. In particular, the deaths of Jesus and Imam Husayn (second son of ‘Ali) continue to serve as sources and symbols of martyrdom, with the passion regularly reenacted within each of these faith systems.

Roman Catholics and Shi’i Muslims offers a strong argument to justify this comparative presentation of two distinct yet similar faith systems. If there is a weakness, it lies in the fact that Roman Catholicism and Shi’i Islam each exist in real historical contexts, within which they each evolved in relation to chang-ing political, social, and economic conditions. For Shi’ism, major challenges included the establishment of the Isma’ili Fatimid state in Egypt in the 10th century, the restoration of Sunni Orthodoxy in central Islamic lands in the 11th century, and the establishment of Shi’i Islam as a state religion in the 16th century. The challenge for Catholicism was the reshaping of Christianity in the eastern Roman Empire during the Crusades and after the Reformation. These subjects remain untreated, with the exception of the formulation of the Nicene Creed in the 4th century. There are also historical points of contact through which these two faith systems may have had direct influence upon one another, which warrant further study. Bill and Williams' succinctly summarize Islamic philosophical works, which drew heavily upon the Greek corpus, but they scarcely touch upon the profound effect these may have had on the thought of Thomas Aquinas.

There is an index and list of references, notes for each chap-ter, and a useful glossary of Shi’i terms.