And give to the women (whom you marry) their Mahr (obligatory bridal money given by the husband to his wife at the time of marriage) with a good heart, but if they, of their own good pleasure, remit any part of it to you, take it, and enjoy it without fear of any harm (as Allah has made it lawful).
Chapter 4 An-Nisā’ : Verse 4
Giving the Dowry is Obligatory
`Ali bin Abi Talhah reported Ibn `Abbas saying, Nihlah, in Allah’s statement, `Ali bin Abi Talhah reported Ibn `Abbas saying, Nihlah, in Allah’s statement,
(And give to the women (whom you marry) their Saduqat Nihlah) refers to the dowry. Muhammad bin Ishaq narrated from Az-Zuhri that `Urwah said that `A’ishah said that `Nihlah’ means `obligatory’. Muqatil, Qatadah and Ibn Jurayj said, `Nihlah’ means `obligatory’ Ibn Jurayj added: `specified.’ Ibn Zayd said, “In Arabic, Nihlah, refers to what is necessary. So Allah is commanding: Do not marry unless you give your wife something that is her right. No person after the Prophet is allowed to marry a woman except with the required dowry, nor by giving false promises about the dowry ﴿intended﴾.” Therefore, the man is required to pay a dowry to his wife with a good heart, just as he gives a gift with a good heart. If the wife gives him part or all of that dowry with a good heart, her husband is allowed to take it, as it is lawful for him in this case. This is why Allah said afterwards,
(But if they, of their own pleasure, remit any part of it to you, take it, and enjoy it without fear of any harm.)