What is the Sharee‘ah ruling on a person who says that Islam is the religion of only one wife?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

If the question is about a person’s belief that polygyny is not at all permissible in Islam, such belief means that he disbelieves in the Quran and the Sunnah. Allaah The Almighty Says (what means): {Marry those that please you of [other] women, two or three or four.} [Quran 4: 3]

It is also authentically established that the Messenger of Allaah, sallallaahu ‘alayhi wa sallam, the Companions and the Taabi‘is practiced polygyny.

Consequently, a Muslim who denies the permissibility of polygyny in Islam is an apostate. If such a person, however, concedes the permissibility of polygyny in Islam, but says that having one wife is the original ruling and that polygyny should be practiced only in case of need or necessity, and so on, he is not judged as an apostate. This issue is subject to difference in opinions and Ijtihaad (personal reasoning).

Allaah Knows best.