Chapter on the Dower
His statement: “The dower” is the compensation that becomes due through a marriage contract or through what is treated as equivalent to it.
Our saying, “a marriage contract,” is clear; its conditions, pillars, and what is required in it have already been discussed.
Our saying, “what is treated as equivalent to it,” includes intercourse by mistake—for example, when a man marries a woman and consummates the marriage with her, then it becomes clear that she is his foster sister. In that case, the dower becomes due because of the intercourse, since this intercourse was not unlawful according to the man’s understanding: it did not become clear that she was his foster sister until after the contract and the intercourse.
It is called a ṣadāq because offering it demonstrates the husband’s sincerity in seeking this woman. A person can only give up something dear for what is comparable to it or dearer. For this reason, giving wealth to a poor person is called ṣadaqah (charity), for it shows the sincerity of the giver: the reward he hopes for is dearer to him than the wealth he has given.
The dower has many names because people deal with it so frequently. Among its names are mahr (dower), ajr (payment), and niḥlah (marital gift).
Usually, whatever is frequently spoken of among people has several names. Thus, they say that no creature has more names than the cat. Its names include bās, qiṭṭ, and so forth. It has many names because, as the Prophet ﷺ said: