Essay zu Dewarim 23:2

A curious list of those not counted as part of the “holy people”: one who cannot reproduce, one born of a forbidden union, and a descendant of two of Israel’s traditional enemies to the east. In contrast, the Edomites, Israel’s “cousins,” are permitted into the community after a waiting period. While scholars have tried to date these passages on the basis of specific historical events, such attempts are probably fruitless.