What is the ruling on marriage if the two parties agree upon preconditions – such as the husband not traveling with his wife, for example – by way of a promise, not a condition, and is this view adopted by the Hanbalis or other Mujtahids?

Conditions in marriage are divided into three categories:

1. Conditions that must be fulfilled: These are conditions whose benefit and advantage accrue to the wife, such as stipulating that he not remove her from her home or travel with her, or that he not marry another woman. The husband is obligated to fulfill these conditions; otherwise, she has the right to annul the marriage.

2. Conditions that invalidate the stipulation but validate the contract: These are conditions that contradict the essence of the contract or entail waiving rights established by the contract, such as stipulating no mahr (dowry) or nafaqa (maintenance), or stipulating no sexual intercourse. Such conditions are invalid, but the contract itself remains valid.

3. Conditions that invalidate the marriage from its root: These are conditions that invalidate the entire marriage, such as temporary marriage (Nikah (definition) al-Mut'ah), conditional marriage, or stipulating an option (for either party to unilaterally terminate the marriage).

If both parties agree that what they mention is a "promise" and not a "condition," then the dispute among jurists does not apply to it. Fulfilling a promise is a religious obligation unless it involves something forbidden. The difference between a valid condition and a promise is that failure to fulfill a condition grants the wife the right to annul the marriage, whereas failure to fulfill a promise incurs sin upon the husband without granting the wife the right to annulment.