Both Judaism and Christianity teach charity and forgiveness to the personal enemy, as well as love to the sinner. Their differences center on the proper attitude towards political and religious foes: whereas Christianity acknowledges only the religious enemy, Judaism only recognizes the political enemy. Since, for Judaism, it is axiomatic that all pious gentiles are saved, it cannot admit the notion of a religious foe. Consistent with the principle that her kingdom is not of this world, Christianity does not acknowledge political enemies. In its place, it introduced a new class of foe: the religious enemy.
José Faur, “Jewish and Western Historiographies: A Post-Modern Interpretation”, Modern Judaism 12:1 (February 1992), 32.