Almost 100 people were killed recently when a suicide bomber targeted Shiite Muslim pilgrims in Pakistan. Closer to home, a Sufi cleric's plans to build an Islamic center near Ground Zero have ignited controversy that seems inextinguishable.
Clearly Islam is not monolithic. But what are the differences within the religion, and how deeply do they run?
Although the majority of Muslims are Sunnis, Shiites are the majority in Iran and Iraq, where they were persecuted by Saddam Hussein. The schism between the groups dates to 632, when a controversy arose over the successor to Muhammad.
The Sunnis believe that Muhammad did not designate a successor. But the Shiites believe he did: his cousin and son-in-law, Ali. They also believe that Ali's authority was usurped by the first three caliphs: Abu Bakr and Umar ibn a-Khatab, both fathers-in-law of Muhammad, and Uthman ibn Affan, also a son-in-law. Unlike Ali, none of the men were blood relatives of Muhammad. This was a point of contention for Ali's supporters, who believed that the succession should be hereditary.
After Uthman's assassination in 656, Ali became leader, but discord erupted into civil war. He fought and defeated opponents, one of whom was Aisha, Muhammad's third wife and Abu Bakr's daughter.
After Ali's assassination in 661, Sunni caliphs regained power for more than 20 years. Ali's son, Hussein, fought them and was killed by Sunnis at Karbala, in Iraq. Scholars say that his death, which the Shiites consider martyrdom, helped transform a political movement into a religious one.
Shiites and Sunnis share the Quran but have different collections of the hadith, which are the traditions and deeds of Muhammad. Shiites believe that the imams are the source for the hadith. Sunnis believe the hadith come from the Prophet's companions.
"Because the Shiites gave their imams a higher level of spiritual and political authority than the Sunnis did to the other companions of Muhammad, the Shiite religious scholars have had greater authority in the lives of Shiites than Sunni religious scholars have had in the life of Sunnis," says Robert J. Riggs, a visiting assistant professor of history at Franklin & Marshall College in Lancaster, Pa.
The sects use different sources to settle matters not directly addressed in the Quran or in the hadith. The Sunnis weigh community consensus; the Shiites rely on the infallibility of the imams.
"For Sunni Muslims, since there's no real central authority, decisions about proper Islamic practice take place at a local level," says Keith David Watenpaugh, an associate professor of modern Islam, human rights and peace at the University of California, Davis. "[Shiite] Muslims have a top-down approach. They spend a lot of time training [religious scholars], who go through rigorous years of instruction in law and theology."
Sufi, on the other hand, is a contemplative school of Islam that aims to develop an individual's consciousness of God though chanting, recitation of litanies, music and physical movement. Practitioners belong to different tariqa, or orders, that are described as "sober" -- restrained in religious practice -- or "drunk," open to achieving religious ecstasy.
"For Sufis, what's important is approaching the inner meaning of God through mysticism. They try to reach an understanding of the hidden meanings of the world," Watenpaugh says. "They tend to be less wedded to an orthodox reading of the Quran. As a consequence, they have an open relationship with other religions."
Clearly Islam is not monolithic. But what are the differences within the religion, and how deeply do they run?
Although the majority of Muslims are Sunnis, Shiites are the majority in Iran and Iraq, where they were persecuted by Saddam Hussein. The schism between the groups dates to 632, when a controversy arose over the successor to Muhammad.
The Sunnis believe that Muhammad did not designate a successor. But the Shiites believe he did: his cousin and son-in-law, Ali. They also believe that Ali's authority was usurped by the first three caliphs: Abu Bakr and Umar ibn a-Khatab, both fathers-in-law of Muhammad, and Uthman ibn Affan, also a son-in-law. Unlike Ali, none of the men were blood relatives of Muhammad. This was a point of contention for Ali's supporters, who believed that the succession should be hereditary.
After Uthman's assassination in 656, Ali became leader, but discord erupted into civil war. He fought and defeated opponents, one of whom was Aisha, Muhammad's third wife and Abu Bakr's daughter.
After Ali's assassination in 661, Sunni caliphs regained power for more than 20 years. Ali's son, Hussein, fought them and was killed by Sunnis at Karbala, in Iraq. Scholars say that his death, which the Shiites consider martyrdom, helped transform a political movement into a religious one.
Shiites and Sunnis share the Quran but have different collections of the hadith, which are the traditions and deeds of Muhammad. Shiites believe that the imams are the source for the hadith. Sunnis believe the hadith come from the Prophet's companions.
"Because the Shiites gave their imams a higher level of spiritual and political authority than the Sunnis did to the other companions of Muhammad, the Shiite religious scholars have had greater authority in the lives of Shiites than Sunni religious scholars have had in the life of Sunnis," says Robert J. Riggs, a visiting assistant professor of history at Franklin & Marshall College in Lancaster, Pa.
The sects use different sources to settle matters not directly addressed in the Quran or in the hadith. The Sunnis weigh community consensus; the Shiites rely on the infallibility of the imams.
"For Sunni Muslims, since there's no real central authority, decisions about proper Islamic practice take place at a local level," says Keith David Watenpaugh, an associate professor of modern Islam, human rights and peace at the University of California, Davis. "[Shiite] Muslims have a top-down approach. They spend a lot of time training [religious scholars], who go through rigorous years of instruction in law and theology."
Sufi, on the other hand, is a contemplative school of Islam that aims to develop an individual's consciousness of God though chanting, recitation of litanies, music and physical movement. Practitioners belong to different tariqa, or orders, that are described as "sober" -- restrained in religious practice -- or "drunk," open to achieving religious ecstasy.
"For Sufis, what's important is approaching the inner meaning of God through mysticism. They try to reach an understanding of the hidden meanings of the world," Watenpaugh says. "They tend to be less wedded to an orthodox reading of the Quran. As a consequence, they have an open relationship with other religions."