Nowhere is the singularity of biblical ethics more evident than in its treatment of the issue that has proved to be the most difficult in the history of human interaction, namely the problem of the stranger, the one who is not like us. Most societies at most times have been suspicious of, and aggressive toward, strangers. That is understandable, even natural. Strangers are non-kin. They come from beyond the tribe. They stand outside the network of reciprocity that creates and sustains communities. That is what makes the Mosaic books unusual in the history of moral thought. As the rabbis noted, the Hebrew Bible in one verse commands, "You shall love your neighbor as yourself," but in no fewer than 36 places commands to "love the stranger."

Jonathan Sacks, The Dignity of Difference