males are circumcised. In exile the challenge is to be willing to stand out by such practices. Genesis helps the exiles to meet this challenge by asserting that these practices have an authority even greater than the Mosaic law. Circumcision goes back to Abraham (Gen 17). The kosher law goes back to Noah (Gen 9:4). And the sabbath goes back to the pattern of God’s own activity at creation: God did his week’s work and then rested (Gen 2:2). The importance of these marks of Israel is thus heavily underlined.