Do to others: Since the 18th century, Jesus’ saying, “Do to others whatever you would have them do to you,” has been known as the Golden Rule. The rule, in essence, encapsulates the Law and the Prophets (v 12b). This is not distinctly Christian as in antiquity there were many variations of this saying, although in the negative form. Rabbi Hillel, a contemporary of Jesus, is reported to have said, “What is hateful to you, do not do to your fellow creatures.” The negative formulation could also be found among the sages of other faiths. On the other hand, the Law and the Prophets—or the essence of the Scriptures—would be summarized in other ways. Jesus himself says that the commandment of love of God and neighbor is the first and the sum of all the commandments (Mk 12:30-31). And the apostle Paul declares, “Love does no evil to the neighbor; hence, love is the fulfillment of the Law” (Rom 13:10).
The cultural value behind the Golden Rule is reciprocity, a give-and-take exchange that takes place between individuals and groups. The first kind of reciprocity is sharing without expecting something in return. This happens in the family: parents provide for their children, expecting to be repaid only by love and gratitude (vv 9-10). The second kind is doing good in the hope of being reciprocated with another good. Thus a man invites his neighbor to a meal in the hope of being invited in the future, or lends to his neighbor in the hope of being able to borrow from the same person. The third kind of reciprocity is to do good to a stranger, expecting no return. This is the basis of the Middle-Eastern custom, even the sacred duty, of providing hospitality to strangers (see Gn 19:5).