Added 1.4.16 (Original convo 12.22.15)
I'm really curious about the different theological traditions of Islam. What can you tell me?
This one could probably be answered in various ways and extensively, but I'll try to at least frame a couple directions that I think it could go . . . and then I'll give some examples of actual differences among sects.
First way to take the question: From within the central line of scholarship in Islam which demonstrably aligns with al-Qur'an, authentic ahadith, and the unadulterated practice and understanding of the early Muslims, there really isn't a significant variation in theology. We sometimes use names for that scholarship and understanding, like Ahlus-Sunnah wal-Jam'ah, but they are better known for their traits and beliefs in that we see people can easily misue labels. In any case, the center of theology in Islam is at-Tawheed, the Oneness of Allah in His actions, attributes, and worthiness of worship. At-tawheed and the other central tenants of belief, what we call aqeedah, are generally matters of consensus in authentic scholarship, as is Shari'ah, or law.
The variation in the central line of scholarship enters the picture when it comes to fiqh, or Islamic jurisprudence. Fiqh entails practical matters of implementation of the Shari'ah. To say it another way, scholars will be of various schools of thought or various opinions when it comes to religious practices and circumstantial application of the law (the most famous schools of thought being Maliki, Hanafi, Shafi'i, and Hanbali). However, their opinions and ijtihaad (interpretive rulings) hold validity only in as much as their bases are evidenced from al-Qur'an and as-Sunnah (or analogies from them, called qiyaas, as well as ijmaa', which is scholarly consensus). These differences of opinion are called ikhtilaaf, which actually came up even at the time of the Prophet, peace on him. For example, the Prophet, peace on him, gave the order to a group of his companions that they should not pray Asr (the third prayer of the day) except in such and such a place. While on their way the time of the fourth prayer was coming near, meaning the time in which Asr should be prayed was nearing a conclusion before they had gotten to their destination. Some of the companions prayed midway in the journey, interpreting the Prophet's statement to mean that they should hurry, while the remainder interpreted the Prophet's statement to the letter and waited to pray until the group reached the destination. Later on they came to the Prophet, peace on him, and asked which was right. He gave tacit approval to both. Therefore, ikhtilaaf is considered a normal part of the religion and the correct manner is to leave discussion of matters of ikhtilaaf to those of knowledge and not to artificially make them points of conflict or difference when the intention in all those cases is to do what is correct.
There are times—prolifically so in the past—that Muslims have mistakenly made issues of ikhtilaaf reasons for disunity, but, in general, Muslims follow various rulings side-by-side with each other; all the while, they share unity in their beliefs and intentions and have no trouble finding compatibility so long as their characters are sound and ignorance has not reared it's head. Which leads us to . . .
Second way to take the question: Many groups and individuals do in fact differ in issues of aqeedah, those matters of belief I spoke of upon which there is consensus among the central scholars. As well, some attach practices to Islam which have no resemblance to what the Prophet, peace on him, and the early Muslims did; we call those practices bid'ah, or innovation. That's where sectarianism comes in, which the Prophet, peace on him, forewarned would happen despite it being forbidden. Allah says, "And hold firmly to the rope of Allah (al-Qur'an) all together and do not become divided. And remember the favor of Allah upon you - when you were enemies and He brought your hearts together and you became, by His favor, brothers. And you were on the edge of a pit of the Fire, and He saved you from it. Thus does Allah make clear to you His verses that you may be guided." As well, the Prophet, peace on him, said that every newly invented matter (in religion) is a going astray and a means to the Hellfire. Unfortunately, though, the Muslims have become divided.
Within each group, even among the majority Muslims, there is a lack of unity, probably linked in great part to ignorance and lack of sound priorities. What I can say form a sympathetic standpoint regarding sectarianism, however, is that what an individual believes and does is far, far more important than any label. A person might say he is from Ahalus-Sunnah, but he actually follows his whims and desires or neglects to learn what that means. At the same time a Shii might call herself that because she was born in such a family or region even while her core beliefs and general practices are sufficient to overcome minor mistakes such that she is a Muslim. Thus, Sufism, Shiism, and all those other isms are rife with misguidance, but the condition of an individual is more complex than a label, and Allah loves best those who fear and love Him and He loves those who love the truth. Ameen.
As for the actual theology of each sect, then that is an exhaustive matter, but I can give some examples of sectarian beliefs that diverge from the central scholarship: Among the Shii are those who treat certain religious leaders of the past (like the twelve Imams they list) special praise and powers to the point that they compete with the leadership of the Prophet Muhammad, peace on him, or beyond that, their traits overlap with the attributes of Allah (i.e., giving divine characteristics to humans). Among the Sufis, as another example, are those who blindly follow a shaykh or teacher such that they do the bidding of the teacher and take his rulings without evidence from al-Qur'an or ahadith. A famous trait of a category of deviants called khawaarij is making takfeer, or deeming someone a disbeliever, on account of major sins, a clear excess as the Prophet, peace on him, and his companions still regarded such as Muslims. Another category of sects is Mutazites, and one trait they had is to say, for example, faith does not go up and down, whereas Allah mentions in al-Qur'an what increases faith and the central scholars explain, based on many evidences from both al-Qur'an and ahadith, that faith goes up with good actions and goes down with bad actions. And we can go on and on and on and really, I mean we can go on with this for volumes upon volumes and it's all widely published in the books of the scholars.
What I'll add, though, is that much of the mainstream use of the labels for various sects, in my opinion, are often basically geopolitical terms more than useful descriptions of what individuals believe or do relative to the authentic message. Further, there are divergent beliefs and practices that nullify a person's Islam and there are those which are merely defects. Both categories can be found among people from any sect in Islam, including from among the majority Muslims who don't openly ascribe to a clearly divergent sect. The wonderful thing is that the original path Allah laid out for us via His Messenger, peace on him, is still intact and available for those who are sincere and diligent to gain knowledge and work on themselves to at least move in the right direction. May Allah guide us all. Ameen.
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