This Ayah contains many rulings, including the use of the word Nikah for the marriage contract alone. There is no other Ayah in the Qur'an that is clearer than this on this point. It also indicates that it is permissible to divorce a woman before consummating the marriage with her.
الْمُؤْمِنَـتِ
(believing women) this refers to what is usually the case, although there is no difference between a believing (Muslim) woman and a woman of the People of the Book in this regard, according to scholarly consensus. Ibn `Abbas, may Allah be pleased with him, Sa`id bin Al-Musayyib, Al-Hasan Al-Basri, `Ali bin Al-Husayn Zayn-ul-`Abidin and a group of the Salaf took this Ayah as evidence that divorce cannot occur unless it has been preceded by marriage, because Allah says,
إِذَا نَكَحْتُمُ الْمُؤْمِنَـتِ ثُمَّ طَلَّقْتُمُوهُنَّ
(When you marry believing women, and then divorce them) The marriage contract here is followed by divorce, which indicates that the divorce cannot be valid if it comes first. Ibn Abi Hatim recorded that Ibn `Abbas, may Allah be pleased with him, said, "If someone were to say, `every woman I marry will ipso facto be divorced,' this does not mean anything, because Allah says:
يأَيُّهَا الَّذِينَ ءَامَنُواْ إِذَا نَكَحْتُمُ الْمُؤْمِنَـتِ ثُمَّ طَلَّقْتُمُوهُنَّ
(O you who believe! When you marry believing women, and then divorce them....)." It was also reported that Ibn `Abbas, may Allah be pleased with him, said: "Allah said,
إِذَا نَكَحْتُمُ الْمُؤْمِنَـتِ ثُمَّ طَلَّقْتُمُوهُنَّ
(When you marry believing women, and then divorce them.) Do you not see that divorce comes after marriage" A Hadith to the same effect was recorded from `Amr bin Shu`ayb from his father from his grandfather, who said: "The Messenger of Allah ﷺ said:
«لَا طَلَاقَ لِابْنِ آدَمَ فِيمَا لَا يَمْلِك»
(There is no divorce for the son of Adam with regard to that which he does not possess.) This was recorded by Ahmad, Abu Dawud, At-Tirmidhi and Ibn Majah. At-Tirmidhi said, "This is a Hasan Hadith, and it is the best thing that has been narrated on this matter." It was also recorded by Ibn Majah from `Ali and Al-Miswar bin Makhramah, may Allah be pleased with them, that the Messenger of Allah ﷺ said:
«لَا طَلَاقَ قَبْلَ نِكَاح»
(There is no divorce before marriage.)
فَمَا لَكُمْ عَلَيْهِنَّ مِنْ عِدَّةٍ تَعْتَدُّونَهَا
(no `Iddah have you to count in respect of them.) This is a command on which the scholars are agreed, that if a woman is divorced before the marriage is consummated, she does not have to observe the `Iddah (prescribed period for divorce) and she may go and get married immediately to whomever she wishes. The only exception in this regard is a woman whose husband died, in which case she has to observe an `Iddah of four months and ten days even if the marriage was not consummated. This is also according to the consensus of the scholars.
فَمَتِّعُوهُنَّ وَسَرِّحُوهُنَّ سَرَاحاً جَمِيلاً
(So, give them a present, and set them free in a handsome manner.) The present here refers to something more general than half of the named dowery or a special gift that has not been named. Allah says:
وَإِن طَلَّقْتُمُوهُنَّ مِن قَبْلِ أَن تَمَسُّوهُنَّ وَقَدْ فَرَضْتُمْ لَهُنَّ فَرِيضَةً فَنِصْفُ مَا فَرَضْتُمْ
(And if you divorce them before you have touched (had a sexual relation with) them, and you have fixed unto them their due (dowery) then pay half of that) (2:237). And Allah says:
لاَّ جُنَاحَ عَلَيْكُمْ إِن طَلَّقْتُمُ النِّسَآءَ مَا لَمْ تَمَسُّوهُنَّ أَوْ تَفْرِضُواْ لَهُنَّ فَرِيضَةً وَمَتِّعُوهُنَّ عَلَى الْمُوسِعِ قَدَرُهُ وَعَلَى الْمُقْتِرِ قَدْرُهُ مَتَـعاً بِالْمَعْرُوفِ حَقًّا عَلَى الْمُحْسِنِينَ
(There is no sin on you, if you divorce women while yet you have not touched them, nor fixed unto them their due (dowery). But bestow on them gift, the rich according to his means, and the poor according to his means, a gift of reasonable amount is a duty on the doers of good.) (2:236) pIn Sahih Al-Bukhari, it was recorded that Sahl bin Sa`d and Abu Usayd, may Allah be pleased with them both, said, "The Messenger of Allah ﷺ married Umaymah bint Sharahil, and when she entered upon him he reached out his hand towards her, and it was as if she did not like that, so he told Abu Usayd to give her two garments." `Ali bin Abi Talhah reported that Ibn `Abbas, may Allah be pleased with him, said "If the dowery had been named, she would not be entitled to more than half, but if the dowery is not been named, he should give her a gift according to his means, and this is the "handsome manner."