Muwatta Imam Malik (Riwayat Yahya)

It is narrated from Hazrat Qa’qa’ bin Hakim that Ka’b al-Ahbar (who was a great scholar among the Jews and then became a Muslim) said: If I did not recite a few words, the Jews (by doing magic) would have turned me into a donkey. People asked: What are those words? Ka’b said: «أَعُوذُ بِوَجْهِ اللّٰهِ الْعَظِيمِ......» That is: “I seek refuge in the Face (i.e., the Essence) of Allah, Who is Most Great—there is nothing greater in greatness than Him—and in the complete words of Allah, which neither the righteous nor the wicked can surpass (i.e., none has more knowledge than them), and in all the beautiful names of Allah, those which I know and those which I do not know, from the evil of that which He has created, originated, and spread.”