The sequence «Abraham, Ishmael, Isaac and Jacob » which we find in the Qurʾān gives the impression that the Prophet of Islam was not completely clear about the genealogy of the patriarchs and that he had taken Ishmael to be the father of Jacob. Whilst the classical Muslim commentators on the Qur ʾ ān corrected this picture by asserting that Ishmael was neither the father nor the grandfather but the great-uncle of Jacob, the Midrash Berechit Rabba (4th-5th century CE) was even freer in his interpretation against the plain meaning of the text, toying with the family relations in the Bible in order to counter Christian claims about the descendence of Abraham. The result is that the Qur ʾ ān has a creative link with the «exegetical jamming » of...