An-Nisa' - 4:4

وَآتُواْ النَّسَاء صَدُقَاتِهِنَّ نِحْلَةً فَإِن طِبْنَ لَكُمْ عَن شَيْءٍ مِّنْهُ نَفْسًا فَكُلُوهُ هَنِيئًا مَّرِيئًا
[4:4]
And give women their dowries as a free gift, but if they of themselves be pleased to give up to you a portion of it, then eat it with enjoyment and with wholesome result.
And give the women (on marriage) their dower as a free gift; but if they, of their own good pleasure, remit any part of it to you, Take it and enjoy it with right good cheer.
And give unto the women (whom ye marry) free gift of their marriage portions; but if they of their own accord remit unto you a part thereof, then ye are welcome to absorb it (in your wealth).