What is the ruling on stipulations that negate essential rights arising from the marriage contract, such as the dowry or maintenance?

Primary text

Stipulations such as agreeing that there will be no dower (*mahr*), no maintenance (*nafaqah*), or that any dower given will be returned by the wife, or that the husband will abstain from intercourse, or refrain from equitable division of nights with other wives, or that the wife must spend on the husband, are void. These conditions contradict the necessary consequences (*muqtada*) of the contract, as they involve forfeiting rights established by the contract before its inception. However, the marriage contract itself remains valid because these void conditions pertain to extraneous matters whose absence does not invalidate the core agreement, similar to specifying a forbidden dower or a situation where the dower is unknown.