Everyone agrees that Judaism was the first monotheistic religion and that it gave rise to the two daughter religions, Christianity and Islam. I would argue that the dominant humanistic aspects of Christianity and the dominant repressive aspects of Islam each derive from distinct aspects of Judaism. It is as if Christianity inherited the humanistic aspects of Judaism and Islam inherited the repressive aspects of Judaism. In doing so, this dichotomy reflects the personality of each of their prophets, Jesus Christ, who supposedly died on the cross for the suffering of others, and Mohammed, who led his army into battle to force his enemies to submit to his belief system. Each of them had a tremendous influence on the subsequent outcome of events within the Christian and Muslim worlds.
In her analysis of Judaism, Karen Armstrong (“A History of God“) points out the existence of different Gods in the Bible with distinct major characteristics, namely the early God YHWH (or Jehovah) who is a “jealous” God, quick to anger and quite violent, as opposed to the later God called “Adonai” (My Lord) who is more understanding and humane. When St. Paul (who was the Jew Saul under a different name) was establishing his new religion (Jesus Christ himself never claimed to be the progenitor of a new religion) and when Mohammed was establishing his new religion, they each selected different strains from within Judaism to reflect and satisfy their own needs.
This does not mean that these religions developed exactly as planned, although Christianity was supposed to be a loving and humane religion (“love they neighbor as thyself”), it turned out in practice to become very repressive and to engender many wars, but fundamentally the message of Christianity was humanistic (even though the message got lost in the exigencies of history). On the other hand, Islam was a repressive and violent religion from the outset, and the war of succession between the Caliphate (the Sunni) and the supporters of Mohammed’s family (the Shia) is still with us and unresolved until today.
It is a if Christianity is similar to the Reform Judaism that has developed in the USA, that is certainly heavily influenced by Christianity, but that has a strong humanistic, liberal bent, that derives from the reform Judaism that developed in Germany prior to the 1930’s and that is endemic in Judaism. Whereas the predominantly totalitarian bent of Islam is similar to the culture of the ultra-Orthodox (haredi) form of Judaism, where what the Rabbi says is more important than independent thinking or democratic values. We often say that the haredi Rabbis are like the Ayatollahs of Iran.
It is noteworthy in this respect that the secular form of government developed mainly in the West as an outgrowth of Christianity, as a result of the separation of Church and State, whereas in Islam there is no such separation between the secular and religious power. In fact in the Muslim world religious power is predominant and secular countries are continually struggling to define themselves. This is evident in the current chaos in the Arab Muslim world.