Summary : A. Language. I. Various positions on the language and style of the Qurʾān. II. The theological (i.e. Islamic) thesis on the language of the Qurʾān. 1. Its general formulation. 2. The Qur'ān on its own language. 3. The superiority of the Arabic language and the excellence of the Koranic language according to the Islamic tradition. 4. The so-called " challenge verses ". 5. The foreitgn words. 6. The problem of the Arabic grammar. 7. The mythical narratives on the superiority of Arabic. 8. The " creation " of a Prophet against his competitors (poets, soothsayers, orators, story-tellers, etc.). II. The hypotheses of the Arabists. B. From language to style. I. The theological (Islamic) thesis on the style of the Qur'ān. 2. The positions of the Arabists on the style of the Qurʾān. a. Some positions until recently. b. The ancient Christian or Syriac connection.