Musnad Abu Ya'la al-Mawsili 153:109

Husayn ibn al-Aswad narrated to us, Abu Usamah narrated to us, Umar ibn Hamzah narrated to us, he said: I heard Salim saying: Abdullah ibn Umar informed us that the Messenger of Allah (may Allah bless him and grant him peace) said: "You will fight the Jews until the stone says: 'O Muslim, this is a Jew behind me, come and kill him.'"