Not only is the logic of belief not necessarily the logic of believers, the use of scripture is itself subject to evolutionary processes.
Educator and reform Muslim Irshad Manji and evolutionary biologist and secular Jew Bret Weinstein have a very thoughtful discussion about violence in scriptures and their different manifestation in (historical) Islam and Judaism. To state the obvious, there is a lot of violence in the Quran and there is a lot of violence in the Torah. Yet rabbinical Judaism, following the end of the Jewish revolts against the Roman Empire, has a very different history of religious violence than does Islam.
Well, than mainstream Sunni Islam. There are versions of Islam that have very similar trajectories to Rabbinical Judaism due to being historically embedded in very similar social dynamics and circumstances.
From Hebrews to Jews
Priestly Judaism (or, more accurately, the Yahweh worship of the Hebrews) was a violent religion. It was not, however, notably more violent than other religions of its time and place. It was also a religion of the Law of God, of law grounded in revelation, whose scriptures readily sanctified violence against other peoples and religions. (Including apostates within their own people.)
The Jewish lands were conquered by the Romans, also a people of Law, but of law explicitly made by humans. Having Roman law, based on very different presumptions than that of the Talmud, effectively override the Law of God was profoundly offensive to Hebrew sensibilities. This periodically led to violent revolts that the Romans put down with their customary brutal thoroughness.
Eventually, the destruction of the Second Temple saw the sacrificial role of the priests abandoned and the religious scholars, the rabbis, become the interpreters of scripture and the officiators of ritual. It also became clear that the Romans really meant it: they were prepared to deport, massacre, crucify and enslave whatever number of Hebrews were required to end revolts against Roman rule.
So, the rabbis evolved a new approach whereby Diaspora Jews were required to follow the Law of God but that law would be interpreted by carefully trained scholars in such a way as to permit the Jewish communities to survive and prosper as minority communities within gentile-dominated polities. Doing so while recognisably remaining themselves by remaining anchored in a tradition already many centuries old and which saw itself as reaching back to Creation itself.
This socially and culturally evolved response to the clash between law grounded in revelation and law explicitly created by humans turned out to have monumental consequences. Christianity, evolving out of Judaism in a very law-concerned Empire, adopted the Roman notion that law, even Church law, was human, while developing its own priesthood.
A few centuries later, Islam adopted law grounded in revelation interpreted by religious scholars. It never developed a priesthood as such.
Meccan Islam took the rabbinical path of how to operate in a polity dominated by non-Muslims. But Muhammad became ruler of Medina, so the head of a polity; a wielder of violence who unified of Arabia by preaching and sword. The archetypal symbol of Muhammad is, after all, his sword. Medinan Islam is a religion of rulership, of dominion.
Sharia, the revelation-grounded system of law which evolved within the Islamic empire, is a system of law with no pre-imperial existence. It is also the only system of law that claims, by its nature, the right to apply to all humans everywhere. For it is the law of the Sovereign of the universe, discovered by trained scholars through the process of fiqh, of Islamic jurisprudence. The difference in one’s fundamental standing as a human being is between those who have voluntarily submitted to Allah’s sovereignty (Muslims), those who have submitted to the rulership of those who have submitted to Allah’s sovereignty, and so His law, (dhimmis) and those who have failed to so submit.
The clash between the Law of God and human law that convulsed the Hebrew lands of the Roman Empire is a clash whose consequences have reverberated across the entire history of Islam and Christendom and down to our present day. When jihadis kill, they do so in the name of the universal sovereignty of Allah.
Moreover, Islam evolved in a polygynous, patrilineal, kin-group pastoralist society. Actually, that is mostly redundant. Almost every pastoralist society has been polygynous, patrilineal and organised via kin groups.
Pastoral societies are polygynous because there is no reason inherent to pastoralism to evolve compulsory single-spouse marriage for elite males. On the contrary, that animals herds can increase undermines attempting to restrict the number of (usually male) heirs, or to maximise investment in the human capital of one’s offspring. That eliminates two powerful pressures for compulsory single-spouse marriage. While the value of extra connections encourages going for more wives, and more children, and so encourages polygyny.
Pastoralist societies are patrilineal because one cannot look after animal herds while minding children, making herding a male activity with the animals being bequeathed to the next generation of males. (So down the patrilineal line.)
Pastoralist societies are kin-group based as animal herds are mobile, so their protection is better managed through strong personal links (rather than territorial ones) that kin can provide, and provide better if related males are raised together.
Hence the social selection pressures operating on pastoralist societies are for them to be polygynous, to be patrilineal and to have strong kin groups. The mobility such societies train people for encourages them to trade (to broaden their access to goods and services) and to raid (to broaden their access to goods and services). Both trading and raiding can improve male access to (sexual and fertility services) by improving their appeal as marriage partners within the society. Raiding also enables the seizing of women from outside the society. With the latter dispensing with any pesky consent difficulties.
The Norse going-a-Viking were repeating this pattern on the seas, rather than across grasslands.
There was a significant pastoralist element to Hebrew society, which is why Jewish tribes flourished in Arabia up until the time of Muhammad. Their example, and the commonality in subsistence circumstances, made it much easier for Islam to adopt and adapt the Jewish model.
But Hebrew society had also incorporated farmers and town dwellers. This gave monolatry (worship of one god) a powerful advantage, as it was a way of unifying farmers, herders and town-dwellers within the same ritual and moral community.
This was particularly advantageous in the Middle East, as it has the most socially permeable ecological boundaries between farming and herding of anywhere in the world. It is the region of the world where farming land and pastureland are most intermingled, both physically and socially, with people shifting from farming to herding and back again, according to circumstances.
This permability likely has a great deal to do with why monotheism is such a distinctive feature of the religious history of the Middle East. Any religious outlook able to unite people across the farming-herding divide had a powerful social selection advantage in the region. Monolatry, and even more monotheism (the claim that there is only one God), was thus adaptively favoured to evolve and prosper in the eco-geographical circumstances of the Middle East.
Islam evolved in a polygynous, patrilineal, kin group, raiding society. Sharia evolved in an imperial polygynous, patrilineal, kin group, raiding society engaged in the most dramatically successful waves of religious conquest in history.
The result is that Sharia not only sanctified polygyny, it also sanctified sexual predation against non-Muslim women. Doing so in the Quran, Hadith and the life of the Prophet, the key sources of Sharia. The 15 references in the Quran to those whom your right hand possess (ma malakat aymanukum) have been canonically taken to permit sex with captured women. Various hadith reinforce this. As does the actions of Muhammad when he ruled Medina, killing the males of defeated tribes and distributing the women and children as slaves to his followers. Hence Sharia holds that the marriage of a woman captured by a Muslim warrior is automatically annulled by the act of capture (obviously, so the captor can have sex with her).
This set up schemata (patterns of belief) and scripts (patterns of action) that have operated across the entire history of Islam, and still have life within mainstream Sunni Islam. Yazidi girls raped by ISIS warriors reported that their rapists cited religious justifications for their acts. Religious justifications that were also reported by the victims of “grooming gangs” in Britain.
A polygynous society, where elite men have extra wives and concubines, generates lower status men who are effectively excluded from the marriage market. One classic response of such societies to this surplus of unattached men is “those people over there have women, take theirs”. A response almost invariably adopted by pastoralist societies and other raiding polygynous societies, such as the Norse. The difference is, Islam sanctified this response. Which had the further advantage of making it much easier to recruit ghazis, holy warriors, to operate on the borders of Islam; to raid infidels and soften the border lands up for the further expansion of Islam. Islam is the only human civilisation explicitly and systematically structured to be violently expansionary: i.e. imperial.
Dominion and practicality
Islam is structured to be an imperial religion of domination. If, however, dominion is not practical, due to being a permanent minority, then such minority versions of Islam are in the same position as post-diaspora Jews: minority followers of the law of God in polities dominated by others. Hence the Ibadis, Ismailis, Alevis and Ahmadi’s generally look very “Jewish” in their behaviour and outlook: concentrating on the cohesion of their communities and avoiding being violent neighbours. (Parsees are an analogous case from outside the Mosaic religions.)
In the right social circumstances, the Quran can turn out to be the basis of much the same social dynamics as the Torah.
The Christian New Testament is considerably less violent in content than the Torah, Tanakh or the Quran. Yet states Christian in religion and culture conquered almost the entire globe. That is because (1) those states competed fiercely, and violently, against each other, evolving to be highly effective states and (2) because imperialism is what states do when they can.
The social dynamics of state competition mattered far more than the relatively pacific content of the Gospels and the Acts.
So, scriptures on their own tell us much less than we might imagine. We have to consider how the use of scriptures evolves in different circumstances, thereby generating various social dynamics. Quite different scriptures can evolve very similar (or at least overlapping) social dynamics.