Golden Rule
Judaism

A rule of reciprocal altruism was stated positively in a well-known Torah verse (Hebrew: ואהבת לרעך כמוך):

You shall not take vengeance or bear a grudge against your kinsfolk. Love your neighbor as yourself: I am the L ORD.

Rashi commented what constitutes revenge and grudge, using the example of two men. One man would not lend the other his ax, then the next day, the same man asks the other for his ax. If the second man should say, "“I will not lend it to you, just as you did not lend to me," it constitutes revenge; if "Here it is for you; I am not like you, who did not lend me," it constitutes a grudge. Rashi concludes his commentary by quoting Rabbi Akiva on love of neighbor: "This is a fundamental principle of the Torah."

Hillel the Elder (c. 110 BCE – 10 CE), used this verse as a most important message of the Torah for his teachings. Once, he was challenged by a gentile who asked to be converted under the condition that the Torah be explained to him while he stood on one foot. Hillel accepted him as a candidate for conversion to Judaism but, drawing on Leviticus 19:18, briefed the man:

What is hateful to you, do not do to your fellow: this is the whole Torah; the rest is the explanation; go and learn.

Hillel recognized brotherly love as the fundamental principle of Jewish ethics. Rabbi Akiva agreed, while Simeon ben Azzai suggested that the principle of love must have its foundation in Genesis chapter 1, which teaches that all men are the offspring of Adam, who was made in the image of God. According to Jewish rabbinic literature, the first man Adam represents the unity of mankind. This is echoed in the modern preamble of the Universal Declaration of Human Rights. And it is also taught, that Adam is last in order according to the evolutionary character of God's creation:

Why was only a single specimen of man created first? To teach us that he who destroys a single soul destroys a whole world and that he who saves a single soul saves a whole world; furthermore, so no race or class may claim a nobler ancestry, saying, 'Our father was born first'; and, finally, to give testimony to the greatness of the Lord, who caused the wonderful diversity of mankind to emanate from one type. And why was Adam created last of all beings? To teach him humility; for if he be overbearing, let him remember that the little fly preceded him in the order of creation.

The Jewish Publication Society's edition of Leviticus states:

Thou shalt not hate thy brother, in thy heart; thou shalt surely rebuke thy neighbour, and not bear sin because of him. 18 Thou shalt not take vengeance, nor bear any grudge against the children of thy people, but thou shalt love thy neighbour as thyself: I am the L ORD.

This Torah verse represents one of several versions of the Golden Rule, which itself appears in various forms, positive and negative. It is the earliest written version of that concept in a positive form.

At the turn of the era, the Jewish rabbis were discussing the scope of the meaning of Leviticus 19:18 and 19:34 extensively:

The stranger who resides with you shall be to you as one of your citizens; you shall love him as yourself, for you were strangers in the land of Egypt: I the L ORD am your God.

Commentators interpret that this applies to foreigners (= Samaritans), proselytes (= 'strangers who reside with you') and Jews.

On the verse, "Love your fellow as yourself", the classic commentator Rashi quotes from Torat Kohanim, an early Midrashic text regarding the famous dictum of Rabbi Akiva: "Love your fellow as yourself – Rabbi Akiva says this is a great principle of the Torah."

In 1935, Rabbi Eliezer Berkovits explained in his work "What is the Talmud?" that Leviticus 19:34 disallowed xenophobia by Jews.

Israel's postal service quoted from the previous Leviticus verse when it commemorated the Universal Declaration of Human Rights on a 1958 postage stamp.
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