And neither were you present on the slope of Mount Sinai when We called Moses. But you are sent as an act of your Lord's Grace, to warn people to whom no Warner has come before you, so that they may reflect. ((32:3), (36:6). Prophet Ishmael, the ancestor of Arabs, cannot be considered a Prophet to them since Children of Ishmael multiplied and inhabited Arabia as the Arab community long after his death. See (2:125) and introduction to Surah 11 Hud).