This statement from Griffiths isn’t necessarily incompatible with the existence of earlier translations of biblical texts in Arabic.
I think it is:
Griffith :
Any earlier versions which may have been made in Arabia prior to Islam have left only faint traces behind them, and were unknown to Christians in the conquered territories
What is unknown does not exist.Christians were not aware, therefore it does not existed for them.
That it existed outside, I'm rather dubious;what is the point of translating Biblical texts if what you translate is not distributed?
To pose the question it is to respond it.
That texts were apparently not available to Muslims doesn’t automatically mean that they weren’t available to the authors of quranic texts a few generations earlier.
Why not. But there is no sources, no souvenirs, etc. With this, I think it should be step aside.
That texts were apparently not available to 8th and 9th century Christians as the literary language of the Near East shifted from Greek, CPA and Syriac to Arabic doesn’t automatically mean that they weren’t available to Arabic speaking Christians elsewhere in the 6th and 7th centuries.
I think yes, it does mean. Not necessarily "automatically ". But with some work in this topic one realizes that it is very unlikely. As there is no source about them, it seems (to me) very implausible that they existed in Arabic. They would have spread for the Christianization of Arabophone people, at least in the West.
The argument that there weren’t any early Arabic translations of biblical texts is a perfectly reasonable hypothesis. I just can’t see that it’s conclusive or that it can be proved.
I (personally) consider that from the moment where there is nothing, like in this case, intellectual constructions have to be put aside. It is not history any more. That it cannot be proved, yes, of course. But it is such implausible for (very) good reasons, that it is necessarily conclusive to construct a landscape of the emergence of the Quran. Furthermore diglossia (Syriac/Arabic) can be argued instead of translation.
Topic: Qur'anic studies today