"Beware that ye take not unto yourselves more wives than two. Whoso contenteth himself with a single partner from among the maidservants of God, both he and she shall live in tranquillity."
[Baha'u'llah, Kitab-i-Aqdas]
"Concerning bigamy, this has been promulgated, and no one must abrogate it. ‘Abdu’l Baha has not abrogated this law. These are false accusations and lies (spread by) the friends..."
"You asked about polygamy. According to the text (nass) of the Divine Book, having two wives is permitted ja’iz). This was never (abadan) prohibited, but it is legitimate and allowed (halal wa mubah)..."
[Amr wa Khalq 4: 174f]
According to Sen McGlinn, the Bab allowed this too. (a wife taking a second husband because of the first husband's infertility)
“... it is true that during the ministry of Bahá'u'lláh, and also during that of Abdu'l-Baha, bigamy was practiced to some degree in the Bahá'í communities of the East.”
- written on behalf of the Universal House of Justice
“...[Bahá’u’lláh] outwardly permitted two wives.”
- Universal House of Justice