Philo: The Special Laws, I

XXII. (110) And besides these commands, he also defined precisely the family of the women who might be married by the high priest, commanding him to marry not merely a woman who was a virgin, but also one who was a priestess, the daughter of a priest, that so both bridegroom and bride might be of one house, and in a manner of one blood, so as to display a most lasting harmony and union of disposition during the whole of their lives. (111) The others also were permitted to marry women who were not the daughters of priests, partly because their purificatory sacrifices are of but small importance, and partly because he was not willing entirely to disunite and separate the whole nation from the order of the priesthood; for which reason he did not prevent the other priests from making intermarriages with any of their countrywomen, as that is relationship in the second degree; for sons-in-law are in the place of sons to their fathersin-law, and fathers-in-law instead of fathers to their sons-in-law.