In the first place, it should be noted that Muslims are always commanded to abide by their stipulations. Highlighting this fact, the first verse of Surat Al-Ma’idah reads: “O ye who believe! Fulfil your undertakings.” (Al-Ma’idah: 1)
The prominent Muslim scholar Dr. Taha Jabir Al-`Alawani, president of the Graduate School of Islamic and Social Sciences and president of the Fiqh Council of North America states:
“When a Muslim makes a commitment in the marriage contract that he will not marry another woman unless after seeking his wife’s consent, he must fulfil this commitment because the Prophet, peace and blessings be upon him, said: “Believers are to abide by their stipulations.” Once a person makes such a commitment, he has no right to go around seeking a second wife without his wife’s knowledge and permission because he has agreed to the terms of the contract.”