Islam is a far more heterogeneous religion than most people are aware. Once you bypass the overly simplistic bifurcations, the startling diversity and theological chaos of the tradition becomes apparent.
There are sizeable Shi'ite sects which believe: in a Trinity of Divine Emanations that incarnate cyclically, including Muhammad and Imam Ali, as well as reincarnation (
Alawites); that the
Yawm al-Qiyāmah (“the Day of
Resurrection”) will not actually take place at the end of time in the afterlife but has already occurred within history, in the person of the
Imam of the Time Hasan in 1164 A.D., which means that sharia law has been abrogated because "
there will be no laws in Paradise"
(Nizari Ismaili) and that the last Imam,
Muhammad al-Mahdi, lives in
occultation and will reappear as the promised
Mahdi (
Twelver Shi'ism).
Sunnism, despite being somewhat more uniform in terms of shariah law given the genesis of all classical schools in a set of early jurisprudential
madhabs, is just as crazy in terms of theological dispute - if not more so, actually, given its decentralised governance model. The Sufi movement with its explicit mysticism and veneration of the
Wali (saints), was born in the Sunni world. Some Sufi schools (which are, again, incredibly diverse theologically) teach the extremely bizarre - by conventional Islamic standards - doctrine of
An-Nūr al-Muḥammadī, or the Muhammadan Light, which posits that Muhammad existed before creation itself and that creation is a manifestation of his primordial
nur or light. Ibn Al-Arabi (1076–1148) and Fariddudin Attar (1145–1221) were prominent advocates, the later having wrote, "
The origin of the soul is the absolute light, nothing else. That means it was the light of Muhammad, nothing else." Most mainline Sunnis would view this as
shirk, or associating partners with God.
Other Sufis, such as Ibn Taymiyyah (1263 -1328) a high-profile scholar of the Hanbali school, condemned widely accepted Sunni-Sufi doctrines such as the
veneration of saints and the
visitation to their tomb-shrines.
And many these groups, view one another as heretics.
That said, Sunni sects are far less amenable - or rather is less able to accommodate or adapt - to secular liberal thought than Shi'ite sects, at least outside the Khomeinist strain post-1979. There is a reason that other than Turkey, very few Sunni countries have embraced secularism or democracy, whereas even the Islamic Republic of Iran - under the most repressive version of Shi'ism - in principle holds elections (albeit with a highly restricted pool of candidates) and tolerates Christians, Zoroastrians and Jews (with confessional representation in the
majles or parliament, so long as Muslims don't convert which is deemed apostasy), whereas Saudi Arabia does not even permit churches to be built and is completely opposed even in principle to electoral democracy. Today, the most consistently secular and liberal - but undemocratic - Islamic-majority country, is the Shia dominant Azerbaijan.
The underlying reasons for this are multiple. One of the most important is that Shia theology is centred around rituals that commemorate their community having been a persecuted "
under-dog" minority, alongside Christians, Zoroastrians and Jews, within the Sunni Umayyad Caliphate and their leader, Imam Husayn, suffering martyrdom for refusing to recognise (in Shia eyes) the tyrannical and unconstitutional authority of the Sunni caliphs, and for Nizaris existing as assassins on the peripheries of huge Sunni empires. Sunni theology, by contrast, is emphasises divine triumphalism and godly victory.
Shi'ism is therefore closer to Christianity in prioritising the rights of victimized minorities and of revolutionary social change in favour of those oppressed by society. Thus in the
Nahj al-Balagha, collected by
Sharif Razi, a
Shia scholar in the Tenth century, we find the following statements attributed to Imam Ali:
Letter 47
Let the eternal Reward and Blessings of Allah be the prompting factors for all that you say and do. Be an enemy of tyrants and oppressors and be a friend and helper of those who are oppressed and tyrannized.
Letter 17
We (Bani Hashim) still own the glory of prophethood (having the Holy Prophet (s) from amongst us). Prophethood which brought equality to mankind by lowering the position of mighty and despotic lords and raising the status of oppressed and humiliated persons. When Allah willed the Arabs to embrace Islam, in large numbers they entered its fold willingly or reluctantly.
You can even see a twisted semblance of this rhetoric in the 1979 Iranian Revolution against the Shah.
So while Islam, in general, has difficulties embracing secular liberal constitutionalism because it is a strongly juristic religious tradition, with a vision of One God and a divinely ordained law for his community on earth, different sects are more or less amenable to it.
Christianity is in fact the progenitor of much of liberal thought in its germinal state, as
@Augustus has been rightly and adroitly contending in this thread. The reason that Christianity was a propitious ground for the emergence of such a political philosophy, is again a complicated issue that one could write books on and indeed many scholars have. In essence, though, a particularly important reason was St. Paul's avowed contention that Jesus's death had somehow abrogated the need to observe the dictates of the Hebraic law. In contrast, St. Paul postulated that there was no longer any objective need for a divinely imposed law for governing society but rather that the true source of "the law" was to be sought in the individual human conscience and the corresponding idea that not everyone would interpret this "natural law" in exactly the same way, meaning that difference in custom, dietary habit, clothing and civil or criminal matters had to be tolerated and could be amended in accordance with human need:
Romans 2: 14-15
Indeed, when Gentiles, who do not have the Law, do by nature what the Law requires, they are a law to themselves, even though they do not have the Law, since they show that the work of the Law is written on their hearts
Romans 14:1-23
Welcome a man whose faith is weak, but not with the idea of arguing over his scruples. One man believes that he may eat anything, another man, without this strong conviction, eats only vegetables. The one who eats meat [that isn't kosher or is sacrificed to animals] should not despise the one who refrains, nor should the vegetarian condemn the meat-eater.
Again, one man thinks some days holier than others. Another man considers them all alike. Let every one be definite in his own convictions. If a man specially observes one particular day, he does so “to God”. The man who eats, eats “to God”, for he thanks God for the food. The man who fasts also does it “to God”, for he thanks God for the benefits of fasting. The faith you have, have as your own conviction before God.
Let us therefore stop turning critical eyes on one another. If we must be critical, let us be critical of our own conduct and see that we do nothing to make a brother stumble or fall.
We should be willing to be both vegetarians and teetotallers if by doing otherwise we should impede a brother’s progress in faith. Your personal convictions are a matter of faith between yourself and God, and you are happy if you have no qualms about what you allow yourself to eat. Yet if a man eats meat with an uneasy conscience about it, you may be sure he is wrong to do so. For his action does not spring from his faith, and when we act apart from our faith we sin.
This is an enormously important idea, because in tandem with Jesus's concept of "
render to Caesar what is Caeser's and to God what is God's" and his abrogation of the ritual-cleanliness laws of kashrut and the criminal justice of the Old Testament (i.e. saving the life of the adulterous woman from being stoned to death in accordance with Deuteronomy), it is the opening salvo of what will become the greatest shift in Western civilization. That is, the decisive movement away from the idea of prescriptive law as being of divine origin and mandating a society structured according to unchanging but cyclical ancestral custom under the rule of God or the gods, in favour of a society in progress towards an idealized state of perfection, in which public and private law becomes a separate discipline from theology, and is deemed to be fundamentally human in origin - a fallible and thus revocable human attempt to encode the intuitions of conscience for a given historical circumstance, as humankind increases in better understanding of natural law.
The Romans and Greeks had not belied this either. For them, Caesar was a living deity from whom the law emanated and the Pontifex Maximus (head of both state and religion), while the Athenians famously executed Socrates for diverging from the laws of the gods as passed down by unchanging ancestral custom.
Only one sect of Islam developed this concept, whether independently of Christian influence or not, and this was the Nizari Ismailis within Shi'ism, who broke free of the constraints of
shariah or externally imposed and prescriptive divine law, in 1164 CE.
As Marshall Hodgson explains:
The end of the rule of taqiyya followed naturally from the coming of the Qâʾim, whose manifest and universal power would make taqiyya unnecessary for the protection of the faithful. But its meaning here was no longer simply the guarding of the inner religious truth of the mission of ʿAlî from prying Sunnî eyes.
All those outer forms which the Shîʿa shared more or less with the Sunnîs had come to be lumped together in popular Ismâʿîlî consciousness as being enforced by taqiyya. In the Qiyâma now the learned Ismâʿîlî tradition, in the person of Ḥasan II, was indirectly admitting the validity of their notion. The lifting of taqiyya was made to involve the rejection of all the outer ritual law.
The imâm was now of his mercy granting permission to live without cult, in the spirit alone, which he had formerly forbidden. The end of the sharîʿa could conceivably have been presented as itself a natural consequence of the Resurrection—and no doubt it was so taken in part: there will be no laws in Paradise.[4]
In other words, St. Paul's innovation only caught on comparatively late (compared with being in the very earliest scriptures of Christianity, the Pauline epistles) in one sect (Nizari) of a single denomination (Shi'ism) of Islam, whereas it is mandatory upon all orthodox Christians.
Unsurprisingly, Nizari Shi'ites remain to this day the most liberal and progressive Muslim sect.
