Musnad Ahmad 1153:2159

'Arim ibn al-Fadl narrated to us, Abu 'Awanah narrated to us, from Hilal ibn Abi Humayd, from 'Urwah ibn al-Zubayr, from 'Aishah, she said: The Messenger of Allah (peace and blessings of Allah be upon him) said during his illness from which he did not recover: "May Allah curse the Jews and the Christians, for they took the graves of their prophets as places of worship." She said: And 'Aishah said: Were it not for that, his grave would have been made prominent, but he feared that it would be taken as a place of worship.