Tobit 4:12
12Beware, my child, of all fornication, and take first a wife of the seed of your fathers. Don't take a strange wife, who is not of your father's tribe; for we are the descendants of the prophets. Remember, my child, that Noah, Abraham, Isaac, and Jacob, our fathers of old time, all took wives of their kindred, and were blessed in their children, and their seed will inherit the land.