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The term “Judeo-Christian” refers to something that has its source in the common foundations of Judaism and Christianity. The Bible includes the Jewish Scriptures of the Old Testament, so the moral foundations laid down in Judaism are upheld in Christianity. The first use of the term "Judeo-Christian ethic" was apparently by the German philosopher Friedrich Nietzsche in his 1888 book The Antichrist: Curse on Christianity. The early uses of the term "Judeo-Christian ethic" referred to the Jewish roots and identity of the early Christian church, but it wasn’t used to speak of a common set of morals until much later.
In 1952, President-elect Dwight Eisenhower, speaking to the Freedoms Foundation in New York, said, "Our sense of government has no sense unless it is founded in a deeply religious faith, and I don’t care what it is. With us of course it is the Judeo-Christian concept, but it must be a religion that all men are created equal." This began the modern use of the term in American political and social circles. From Eisenhower’s day to the present, the term has become particularly associated with political conservatives in America, though there are much broader applications. In our American military schools, it is commonly taught that the modern rules for war, like the protection of captives and non-combatants, are based on biblical themes. American jurisprudence is firmly based in Judeo-Christian ethics and celebrates that fact with a variety of artwork throughout Washington, D.C. In the House of Representatives there are 23 marble relief portraits of great lawgivers, including Moses, who is given the central point of focus. The sculptures over the main entrance to the Supreme Court building are centered on Moses with the Ten Commandments, and there are several other representations of Moses and the Ten Commandments in various places throughout the building.
Though there are many aspects to the Judeo-Christian ethic, some of the more common ones are the sanctity of human life, personal responsibility, a high regard for marriage, and compassion for others. Much of what is best in Western civilization can be directly attributed to the Judeo-Christian ethic. Historian Thomas Cahill, in pointing out the common themes of Christianity and Judaism, said, “The heart of the Torah is not obedience to regulations about such things as diet—what one may eat, whom one may eat with, how one must prepare oneself beforehand—but to tzedakka, justice like God’s Justice, justice toward the downtrodden.” The foundations of the Judeo-Christian ethic can be summarized in the “Golden Rule” which Jesus taught His disciples in Matthew 7:12, “So in everything, do to others what you would have them do to you, for this sums up the Law and the Prophets.”