The Kitáb-i-Aqdas - The Most Holy Book
Index term: Contentment
k63.
God hath prescribed matrimony unto you. 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. And he who would take into his service a maid may do so with propriety. Such is the ordinance which, in truth and justice, hath been recorded by the Pen of Revelation. Enter into wedlock, O people, that ye may bring forth one who will make mention of Me amid My servants. This is My bidding unto you; hold fast to it as an assistance to yourselves.
k66.
No marriage may be contracted without payment of a dowry, which hath been fixed for city-dwellers at nineteen mithqáls of pure gold, and for village-dwellers at the same amount in silver. Whoso wisheth to increase this sum, it is forbidden him to exceed the limit of ninety-five mithqáls. Thus hath the command been writ in majesty and power. If he content himself, however, with a payment of the lowest level, it shall be better for him according to the Book. God, verily, enricheth whomsoever He willeth through both heavenly and earthly means, and He, in truth, hath power over all things.
n89.
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.
While the text of the Kitáb-i-Aqdas appears to permit bigamy, Bahá'u'lláh counsels that tranquillity and contentment derive from monogamy. In another Tablet, He underlines the importance of the individual's acting in such a way as to "bring comfort to himself and to his partner". 'Abdu'l-Bahá, the authorized Interpreter of the Bahá'í Writings, states that in the text of the Aqdas monogamy is in effect enjoined. He elaborates this theme in a number of Tablets, including the following:

Know thou that polygamy is not permitted under the law of God, for contentment with one wife hath been clearly stipulated. Taking a second wife is made dependent upon equity and justice being upheld between the two wives, under all conditions. However, observance of justice and equity towards two wives is utterly impossible. The fact that bigamy has been made dependent upon an impossible condition is clear proof of its absolute prohibition. Therefore it is not permissible for a man to have more than one wife.

Polygamy is a very ancient practice among the majority of humanity. The introduction of monogamy has been only gradually accomplished by the Manifestations of God. Jesus, for example, did not prohibit polygamy, but abolished divorce except in the case of fornication; Muhammad limited the number of wives to four, but making plurality of wives contingent on justice, and reintroducing permission for divorce; Bahá'u'lláh, Who was revealing His Teachings in the milieu of a Muslim society, introduced the question of monogamy gradually in accordance with the principles of wisdom and the progressive unfoldment of His purpose. The fact that He left His followers with an infallible Interpreter of His Writings enabled Him to outwardly permit two wives in the Kitáb-i-Aqdas but uphold a condition that enabled 'Abdu'l-Bahá to elucidate later that the intention of the law was to enforce monogamy.
q26.
 
Question: Concerning the dowry.
Answer: Regarding dowry, the intention of contenting oneself with the lowest level is nineteen mithqáls of silver.
q38.
 
Question: Concerning divorce, which must be preceded by a year of patience: if only one of the parties is inclined toward conciliation, what is to be done?
Answer: According to the commandment revealed in the Kitáb-i-Aqdas, both parties must be content; unless both are willing, reunion cannot take place.