Arabs and Christians - The Beginning

I caught a book and reading its description, a thought came to me.

It's called Arabic Christianity in the Monasteries of Ninth-Century Palestine, published by Ashgate Variorum in 1992. The author is Sidney H. Griffith of the Catholic University of America, USA.

This is the description:

The history of Christian literature took a new turn in the 8th century when monks in the monasteries of Palestine began to write theology and saints’ lives in Arabic; they also instituted a veritable programme for translating the Bible and other Christian texts from Greek (and Syriac) into the language of the Qur’an, the lingua franca of the Islamic caliphate. This is the subject of the present volume. Two key factors leading to this change, as Professor Griffith indicates, were that the confrontation with the developing theology of Islam created a direct need for apologetics to face this new religious challenge in its own language; and, second, simply that as the memory of Byzantine power waned, so too did the knowledge of Greek. Issues of particular interest in this apologetic literature are those of the freedom of the will, a key topic in the controversies between Melkites and Muslims, and of the legitimacy of icon veneration, a subject of great contemporary concern at the time of Iconoclasm in the Byzantine Empire.

Admittedly, I am not a scholar of that period but, in a logical approach, one could ask this question:

if Arabs were "always resident in Palestine", as the propaganda claim is made, why did a need for all this appear only in the 8th century, some 150 years after the appearance of Islam?  Was Arabic a 'foreign language' in that geographical area even if Islam was relatively new?

True, the Byzantine empire disappeared and with it the main lingua franca but that was already as early as 614. Moreover, Christianity had been around for centuries and if Arabs lived in the country in any number, they would have known all the theology by now. They were pagans until Muhammed and so were even a better 'target' for Christianity.  Even the rise of Islam in the early 7th century would have provided enough previous time and a need for such translations.

Could it be that in the Land of Israel the presence of Arabs was minimal? And that there was no need for the local monks to engage them theologically?

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