Rabbi Saadia Gaon - Talmudic Rabbi or Islamic Heretic?

 Saadia Gaon has a number of different hats, and is seen in different ways across the Jewish world.

For Talmudic Rabbanites, and also Philosophical Orthodox, he is a giant figure, who was a sort of precursor to Maimonides.

To Karaites, of course he is a bitter enemy, who was the greatest opponent of Karaim. 

Indeed, he also had huge controversies with other Rabbanite leaders on all sorts of things.

However, his malfeasance and violation of the Torah has now been exposed, in that he presents the Islamic falsification of the Parah Adumah - Red Heifer -  in his own Arabic  "translation" [falsification] of the Torah.   This is because the Quran misinterprets the Torah, and instead  claims that the Heifer in question was not Red but yellow!  Saadia Al  Fayyumi  repeats this false interpretation of the Torah in his  tragic-comic Bible commentary:

see https://www.kotzkblog.com/2018/11/202-rav-saadia-gaon-and-his-road-to.html

In the Qur’an, a parallel to the ‘Red Heifer’ is described[19]: The Children of Israel ask Moses to clarify details of the cow to be sacrificed. Moses responds that it should be middle-aged, unblemished, never used for work and the pleasing colour of 'tsafra', yellow (not red).

Freidenreich writes:

“There is, however, one significant departure from the [Hebrew[20]] biblical text: according to every manuscript and edition of the Tafsir which I have been able to examine, the color of the cow is safra [yellow[21]], the qur’anic word used to describe the cow’s color. It appears that Saadiah considers the red heifer to be yellow.”

Bamidbar 19

Thus the great Rabbinic anti-Karaite figure is indeed not even an "Orthodox" Rabbi, but sadly an Islamised syncretic heretic.