Yevamot 55 - 61 Who Committed Bigamy? A kohen gadol, because of
his sacred status, is severely restricted in regard to whom he
may marry. A widow, a non-virgin and even a virgin bogeret (a
girl half-year past puberty which usually takes place at age 12)
are all forbidden to him, in addition to the divorcee and other
women forbidden even to regular kohanim. How about bigamy? May a
kohen gadol, according to Torah law, have more than one wife
just like every other Jew? (The ban on polygamy was instituted
by rabbinic decree almost a thousand years ago.) In Mesechta
Yoma (13a) we find that he may not be married to two women while
performing the Beit Hamikdash service on Yom Kippur. "He shall
atone for himself and for his household" says the Torah (Vayikra
16:11) which implies, through the use of the singular term, that
he can have only one wife, not two households. Although this
seems limited to Yom Kippur, Rambam (Laws of Forbidden Relations
17:13) rules that a kohen gadol may never be married to two
women at the