There is a fundamental principle of Judaism that accounts for all Jewish ethics, including the obligation to love your neighbor as yourself. The Talmudic sage Ben Azzai suggests that this axiom is the Torah's statement that "God created the human being in God's image ... man and woman God created them." The Babylonian Talmud (Sanhedrin 37a) spells out the implications of this concept. Judaism holds that--to paraphrase the American Declaration of Independence--all humans are created in the image of God, and therefore they are endowed by their Creator with certain inalienable rights and dignities, among which are infinite value, equality and uniqueness. Let's explore what these three concepts really mean.
INFINITE VALUE: An image of man has a finite value. A Picasso sold for $30,000,000 plus; a Van Gogh for $82.5 million. But an image created by God is worth incomparably more; it is of infinite value. That is why the Talmud states that "To save one life is equivalent to saving a whole world."
If a life is infinitely valuable, then it must be treated with great concern and care. No precious work of art would be left outside, exposed to the elements. Thus no image of God should ever be allowed to lie on the street, homeless and freezing during winter. Similarly, it is worth spending hundreds of thousands, and indeed millions of dollars, to medically treat and save the life of an infinitely valuable person--meaning, everyone.
EQUALITY: In the Jewish tradition, God is described in images ranging from a powerful warrior to a comforting mother. But it is understood that no image is literal or fixed, and no image is intrinsically superior to the other. To present an image of God as the preferred (or fixed) image of God is idolatry. All images of God (that is, all humans) are equal. Thus the claim that whites are superior to blacks, or males are preferred to women, or members of one religion are truly the image of God and the others are not, is equivalent to idolatry.
The world that we inhabit degrades these fundamental dignities. Poverty and discrimination, legalized slavery and oppression, cultural stereotyping, and human neglect are rampant--but they are incompatible with the dignities of the image of God. Therefore, the Jewish tradition insists that this status quo be fundamentally restructured. We are commanded to work for tikkun olam, to perfect and transform the world until it fully respects the image of God in every human being. We must overcome poverty and hunger, which contradict the infinite value of the individual. We must overcome oppression, because racism, sexism, anti-Semitism, etc., all deny the equality of the other. We must overcome war, which is essentially fought by destroying infinitely valuable images of God with abandon. That is why Isaiah prophesied that "they will beat their swords into plowshares and their spears into pruning hooks and they will not learn war anymore." Isaiah promises that death itself, the ultimate denial of our unique, irreplaceable value, "will be swallowed up in eternity," that is, overcome.
In short, the Jewish dream of tikkun olam includes the ultimate triumph of life over death and the realization of a world in which the full dignities of every individual are respected, nurtured, and developed. This is the Messianic Age in Jewish tradition. Incorporated into Christianity, into Western culture, and into certain variants of Islam, the Jewish revolutionary promise of world transformation has proven to be extraordinarily liberating and shattering of the status quo.
How shall we live until the final perfection is achieved? The answer of Jewish law and tradition is that we should respect the image of God to the maximum possible degree in all our conduct. Tzedakah, the obligation to help the poor and the hungry, stems from the fact that the needy are equal and infinitely valuable. Lashon hara (evil speech) is prohibited (even if the facts asserted are true) because the talk degrades the image of God in another other person. Sexuality is the search for physical and emotional confirmation of our uniqueness and infinite value--as well as that of the other. Thus, all mitzvot (commandments) can be seen as attempts to nurture the dignity of every human being in the image of God. Judaism is the way of life of Jewry, the community that tries to live by this higher standard--until we achieve tikkun olam, the perfection that will make universal the infinite value, equality, and uniqueness of all human beings.