Deuteronomy 23:7,8

Ver. 7, 8. Thou shalt not abhor an Edomite—an Egyptian— The first, the descendants of Esau, the brother of Jacob, were thereby more than neighbours; they were the brethren of the Israelites: and as to the Egyptians, though they at length cruelly oppressed the Jewish nation, yet were their ancestors at first very hospitably received by them; the memory of which benefit God would not permit them to lose. The children begotten of them were to enter into the congregation in the third generation. Though neither the father nor the son could be incorporated into the Jewish community, the grandchild might; for, according to the Rabbis, the grandchildren are the third generation. See Selden de Jure N. & G. lib. 5: cap. 14.

Note; (1.) Near relations, though they may have treated us unnaturally, must be regarded by us with affection still. (2.) The unkindness that we may have received must not cancel our grateful acknowledgment for former favours; we must forget the one, and remember the other.