A Christian is bothering me about the beganing of Islamic history

[Evanaaa]

Assalamu alaikum,I was discussing with a Christian a few days ago, he pointed out that about the beganing of Islam in non Islamic source "The accounts of non-Muslim conquered peoples also conflict with the accounts of traditional Islamic literature. Examining 7th century Byzantine Christian sources commentary on the Arab "immigrants" (Mhaggraye) who were invading and settling in formerly Byzantine territory at that time, historian Abdul-Massih Saadi found the Christians never mentioned the terms "Quran" nor "Islam" nor that the immigrants were of a new religion.They referred to the immigrants in ethnic terms -- "among them (Arabs) there are many Christians...".The Christians used secular or political, not religious terms (kings, princes, rulers) to refer to the Arab leaders. Muhammad was "the first king of the Mhaggraye", also guide, teacher, leader or great ruler. They did however mention the religion of the Arabs. The immigrants' religion was described as monotheist "in accordance with the Old Law (Old Testament)".When the Emir of the immigrants and Patriarch of the local Christians did have a religious colloquium there was much discussion of the scriptures but no mention of the Quran, "a possible indication that the Quran was not yet in circulation." The Christians reported the Emir was accompanied by "learned Jews", that the immigrants "accepted the Torah just as the Jews and Samaritans", though none of the sources described the immigrants as Jews."He also pointed out"Cook reports, though, that this evidence conflicts with the Islamic view in some aspects, associating Muhammad with Israel rather than Inner Arabia, complicating the question of his sole authorship or transmission of the Quran, and suggesting that there were Jews as well as Arabs among his followers"Also he quoted me from crone "Patricia Crone, studying the origins of the Quran, has focused on the examination of the vast body of the Greek, Armenian, Hebrew, Aramaic, Syriac, and Coptic accounts of non-Muslim neighbours of the 7th and 8th centuries which in many cases contradict the traditional Islamic narratives. She argues that the consistency of the non-Muslim sources spread over a large geographic area would tend to rule out a non-Muslim anti-Islamic motive to these sources"Can anyone explain it to me and tell me how to counter this argument ?What is this non-islamic sources are claiming?I think I'll block him but before that I should be clear about my religion.

[Murid]

:wasalam:

Dear sister,
Islam was the religion of every prophet and messenger before.

Jews were more knowledgeable and did practice more probably than some (maybe except Arab) christians and were probably more similar to muslims. Many first converts and sahaba were Jews. Many very learned priests/rabbis did convert.

History is often written as politics and lack of knowledge dictates, and for example, even some 1000 years later it was very known that historians spread great lies about muslims.
Same population of historians tend communicate with themselfs in majority and it that time there were only the east Romans church people historians around who "sold" stories to others as dogmatic.

Islam is a very tolerant religion without enforcement of beliefs and therefore did not raise many anti islamic stances, esoecially because of many converts and shared beliefs