The term Ithna Ashariyah (“T'welver”) or Imami refers to the denomination of Shi‘ism to which the majority of Shi‘as worldwide adhere. The Ithna ʿAshariyah are also known as Imamiyah because of their main tenet regarding the necessity of the imam for the establishment of the ideal Muslim community under divine revelation. The term Shiʿa is generally applied to the Twelvers, despite the fact that there are other factions, such as the Ismaʿiliyah and Zaydiyah, that are also included within Shiʿi Islam.
Characteristic of Twelver Shi‘ism is recognition of the authority of twelve successive imams (spiritual leaders) who were members or descendants of ahl al-bayt (the prophet Muhammad’s immediate family). Their authority is said to have been transmitted over time via the lineage of Muhammad’s daughter Fatima and her husband, Ali ibn Abi Taleb. Also among the characteristics of Twelver Shi‘ism is an emotional attachment to ahl al-bayt that manifests itself in annual rituals commemorating the battlefield death of the imam Hussain, grandson of Muhammad.
The Ithna ʿAshariyah trace their history to the investiture, in Ghadir Khumm (modern-day Juhfah), of ʿAli ibn Abi Talib, the first imam, with wilaya (discretionary authority) by Muhammad after the Prophet 's Farewell Pilgrimage. Following Muhammad 's death in 632, the leadership of the nascent community was assumed by the Prophet 's leading companion, Abu Bakr, but a group of Muslims refused to accept him as caliph. This group constituted the nucleus of the early Shiʿa (“partisans”). They believed that ʿAli was Muhammad 's rightful successor and that those who usurped his right were sinners. This belief marked the genesis of the Shiʿi concept of imamate. Although ʿAli did not assume political authority until after the third caliph, ʿUthman, was murdered in 656, he was regarded by the Shiʿi as the imam, that is, a person qualified to assume temporal and spiritual authority. Following ʿAli 's murder in 660, the imamate continued with Hasan (d. 669) and Hussain (d. 680), the sons of ʿAli and his wife Fatima, Muhammad 's daughter.
The Tragedy of KarbalaEdit
The second most significant event during the formative period of the Ithna ʿAshariyah was the murder of the third imam, Hussain, on the plains Karbala, Iraq, in 680. The Karbala episode provided the Shiʿa with the ethos that led to the distinct Shiʿi belief system, which is constructed around the notion of divinely designated ideal leadership, and the pathos that set the tone of the Ithna ʿAshari religious praxis for posterity. From the Ithna ʿAshari perspective, Karbala became the paradigm for defiance against the unjust authority that culminated in martyrdom (shahadah in the sense of sacrificial death in the path of God). It also marked a shift in the subsequent role of the Shiʿi imam from politically activist upholder of just authority to politically quietist successor of Hussain. The imamate was identified more in terms of the imam 's religious-legal knowledge of Islamic revelation than his activist posture as the redresser of the wrongs committed against the ahl al-bayt (the Prophet 's family).
Imami Shi’ite also links Hussain’s martyrdom at Karbala with the imam’s power to grant intercession in paradise to those who honor Hussain through acts of ritual commemoration.
Theological and Juridical FormationEdit
ʿAli Zayn al-ʿAbidin (d. 714), Muhammad al-Baqir (d. 733), and Jaʿfar al-Sadiq (d. 765), the fourth, fifth, and sixth imams, inaugurated the era of devotional, theological, and juridical formulations of the Ithna ʿAshariyah. Whereas for the Muslim community in general the second half of the eighth century was a period of political and social unrest, for the Shiʿa it was the critical phase of self-definition in the face of competing and politically supported religious expression. The replacement of the Umayyads by the Abbasids in 748 and the political turmoil that ruled in the central lands of the caliphate afforded these imams necessary time to shape the future direction of the Ithna ʿAshariyah. Through the spiritual and intellectual leadership of al-Baqir and al-Sadiq, the Shiʿi developed distinctly Shiʿi Quranic exegesis, through well-documented Prophetic hadiths (reports), including ones related by the imams, and a highly sophisticated juridical tradition, which subsequently earned them a distinct recognition in the larger community as the followers of the Jaʿfari madhhab (rite).
The succeeding imamate of al-Sadiq 's descendants, from Musa al-Kazim (d. 799), the seventh imam, to Muhammad al-Mahdi (disappeared in 874 to return as the Mahdi, “divinely guided” leader of the ummah [community], at the End of Time), the twelfth and last imam, was the most difficult period for the Ithna ʿAshariyah. The imams lived either incarcerated or under surveillance for suspected activities against the caliphate. The Shiʿa were faced with unrelenting ʿAbbasid atrocities and had little or no access to their imams. Under those conditions, the imams appointed their nuwwab (personal deputies), who conveyed their teachings and collected religious dues, such as the khums (originally a fifth of the spoils of war) and zakat (alms), from their followers. This deputyship gradually evolved into the influential religious institution among the Shiʿa that culminated in the wilaya (comprehensive guardianship) of the qualified mujtahid (or faqih; jurist-theologian) under the Qajar and post-Qajar jurists.
During al-Kazhim 's imamate, the concept of an imam in ghaybah (occultation), who continued to direct his community 's affairs through his trusted associates, found theological and legal expression in the hadiths attributed to the imams al-Baqir and al-Sadiq. The requirement of taqiyah (prudential concealment of one 's true belief) as a strategy of survival in the midst of the hostile majoritarian Sunnis also became more pronounced among the Shiʿa at this time. The occultation of the twelfth imam is divided into two forms: the Short (or Lesser) Occultation and the Complete (or Greater) Occultation. During the Short Occultation (874–941), the last imam appointed some of his prominent followers as his “special deputies” to carry on the function of the imamate in religious and social affairs. During the Complete Occultation (941–), the learned jurists among the Shiʿa were believed to have been appointed by the twelfth imam as his “general deputies” to guide believers pending his return.
The period of the general deputies has been dominated by two concerns: first, stabilization of the theological imamate of the twelve imams; and second, consolidation of the juridical and functional imamate of the leading Shiʿi scholars who, being de facto leaders of the Shiʿa, were solely responsible for directing their social and religious life. Whereas the former concern provided the Twelver community with its distinctive creedal identity based on the doctrine of divine justice and infallible leadership of the imams, the latter was instrumental in providing authoritative religious praxis and hierarchical intellectual and spiritual organization to ensure the continuity of the minority community spirit living at times under hostile Sunni power.
The establishment of the Buyid dynasty (932–1055) and its patronage of Shi’ism, despite its support for the continuation of the Sunni caliphate as symbolic of the unity of the majority of the Muslims, created favorable political and social conditions for the Shiʿa. It was intellectually the most productive period of the Ithna ʿAshariyah. Prominent scholars representing the rationalist trend of the Baghdad theologians wrote major works vindicating the imamate of the Hidden Imam. Baghdad was also the point of convergence for the two important centers of Shiʿi hadith, Kufa, and Qom. Qom remained an important center for other cities of Shiʿi learning in Khurasan.
Al-Kulayni (d. 941) and Ibn Babuyah (d. 991), the renowned Imamite traditionists, produced multivolume hadith works that included everything that was needed in formulating the Imamite creed and praxis. Some of the most detailed and systematic treatment of Imamite jurisprudence was undertaken by Shaykh al-Mufid (d. 1023) and his prominent disciples, such as al-Sharif al-Murtaza (d. 1045) and Shaykh al-Ta ’ifah al-Tusi (d. 1067).
In view of the prolonged occultation of the imam, jurists developed a profile of a just Shiʿi authority other than the infallible imam that would manage community affairs. A number of Shiʿi dynasties followed the Buyids, although the first Shiʿi state in Iran was not established until the sixteenth century under the Safavids. Shiʿi jurists had no difficulty in validating the temporal authority of the Safavids. As experts in shariʿa, they justified their own authority as the legally sanctioned wali (guardians) of the community, thereby making themselves responsible for carrying out the obligation of enjoining the good and forbidding the evil. The full implications of such investiture became plain with the establishment of the Qajar dynasty in the late eighteenth century. The role of the Shiʿi religious leadership received fuller elaboration during the nineteenth and early twentieth centuries, until it reached its logical conclusion under Ayatollah Ruhollah Khomeini (1902–1989) in 1980 in the constitutionalization of the wilayat al-faqih (guardianship of the jurist) in the modern nation-state of Iran.
With its rational theology founded on the notion of divine justice and the ideal civil-moral authority of the imam, Shiism during the Safavid and Qajar periods provided the impetus for a renewed interest in Neoplatonist philosophy, more specifically, the Illuminationist theosophy of Suhrawardi. Among the prominent figures whose elaboration of the Avicennian philosophy led them to formulate their own metaphysics were Mir Damad (d. 1631) and Mulla Sadra (Sadr al-Din Shirazi, d. 1640). In jurisprudence, the old tension between the uncritical upholders of the authority of traditions, known as the Akhbari, and the supporters of rationalist methodology, the Usuli, flared up during the later part of the Safavid period and into the Qajar era. The controversy resulted in the resounding victory of the Usuli jurists under the leadership of Vahid Bihbahani (d. 1793) and his disciples. The notion of centralized leadership of the most qualified mujtahid, the marjaʿ al-taqlid, whose authority was institutionalized by the Usuli deduction regarding the necessity of formally pledging obedience to a taqlid (expert) in matters of shariʿa, was also legalized during this period.
Religious Beliefs and PracticesEdit
Unlike the Sunni Five Pillars of Islam, which include both the shahadah (fundamental belief) and religious practice, Twelver Shiism adheres to the usul al-din (principles of religion) and furuʿ al-din (derivatives of religion). The usul expounds the five tenets of the Shiʿi belief system: 1. Tawhid (affirmation of the unity of God); 2. ʿAdl (justice of God); 3. Nubuwah (necessity of prophecy); 4. Imama (necessity of imamate); 5. Maʿad (Day of Judgment). In the principles of tawhid, nubuwah, and maʿad, identified as usul al-Islam (essential for being a Muslim), the Shiʿis in general share a common ground with the Sunnis, although there are differences on points of details. The principles of ʿadl and imamah are peculiarly Shiʿi in that they are regarded as usul al-iman (essential to the faith). Shiʿi belief in God 's justice is similar to that of the Muʿtazilah, who taught that God is infinitely removed from every evil act and from being remiss in doing what is good for humanity. Divine justice also means that God provides humanity with the knowledge of good and evil and creates reason to guide a person to such knowledge. However, there is no guarantee that reason would always seek out the most beneficial way to perfection. Hence, God sends revealed messages through prophets as a complementary source to reason to remind humanity of its fitrah (innate disposition) inclined toward perfection. The principle of imamah is regarded as part of the divinely appointed office of the prophecy to continue the Prophet 's mission of establishing the ideal community on earth.
In Twelver Shi‘ism, the term imam indicates those members of ahl al-bayt who are the true spiritual leaders of the Muslim community regardless of any political recognition or lack thereof extended by the Islamic world at large. The imamate, like the prophecy, is protected from sin and is regarded as a divinely designated office. Through the imamate, survival of religion is guaranteed, hence the Shiʿi belief that “the earth cannot be set aright except by the Imam.” This means that there is an imam in every age, either manifest or concealed, who has the knowledge of the lawful and unlawful in Islam and who calls people to the way of God. There are times when the community can be without a manifest imam; this happens when God is enraged at the people for endangering the imam 's life. Thus, the twelfth imam went into occultation in 874 and will continue to live in this state for as long as God deems necessary; eventually, God will command him to reappear and take control of the world in order to restore justice and equity. During the occultation, the marjaʿ al-taqlid can act on God 's behalf and guide the Shiʿis in their religious and social matters.
The obligation of tawalla (befriending) has led to two important religious practices unique to the Shiʿis: first, the ziara (pilgrimages) to the mashhad (mausoleums) of the imams and their descendants; and second, majalis (devotional gatherings) to mourn the martyrdom of Imam Hussain on Ashura, the tenth day of Muharram, in Karbala. Both these practices have provided the Shiʿi minority with a renewed sense of loyalty to the Prophet 's family. The shrine cities of Karbala, Najaf, Mashhad, and Qom have functioned as the religious centers for the ordinary Shiʿis and learning centers for their mujtahids, who continue to teach in the holy sanctuaries. The Muharram commemoration has fostered among the Shiʿa an identity consonant with their vision of history in which the godly people suffer at the hands of the oppressors until God commands the Mahdi to restore justice and equity on earth.
Love of Ahl al-BaytEdit
Public rituals lamenting the Karbala martyrs are attested as early as the tenth century in Baghdad. The Safavid era, however, witnessed the elaboration of a soteriology that joined ritual mourning with Shi‘ite communal identity. This is attested in a work that became increasingly popular during the reign of the Safavids, Rawdat al-shuhada (The garden of the martyrs), which was written by Hussain Waez al-Kashifi (d. 1504). “Paradise is awarded to anyone,” argues Kashifi, “who weeps for Hussain for the following reason, that every year, when the month of Muharram comes, a multitude of the lovers of the family of the Prophet renews and makes fresh the tragedy of the martyrs.”  “Lovers of the family of the Prophet”: Here Kashifi defines the community of believers not in terms of doctrine but in terms of emotional disposition and ritual activity. His description suggests an important aspect of Imami Shi‘ite identity. At the popular level, from the premodern era through the twenty-first century, Twelver Shi‘as tend to define themselves as those Muslims who excel beyond all others in their love for the Prophet’s family and for the Prophet’s descendants, the imams. ‘his affection is expressed annually in the action of matam (displays of grief for the Karbala martyrs). 
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