Fighting for the Cause of Allah (Jihaad)

Bukhari :: Book 4 :: Volume 52 :: Hadith 176

Narrated 'Abdullah bin 'Umar:

Allah's Apostle said, "You (i.e. Muslims) will fight wi the Jews till some of them will hide behind stones. The stones will (betray them) saying, 'O 'Abdullah (i.e. slave of Allah)! There is a Jew hiding behind me; so kill him.' "