1. Nikah is a great bounty from Allah Ta'ala. The affairs of this world and the hereafter are put in order through marriage. There is a lot of wisdom and many benefits in marriage. A person saves himself from sinning and his heart is put at ease. He does not have any evil intentions and his thoughts do not begin to wander and stray. The greatest virtue is that there are only benefits and only rewards in this. This is because a husband and wife's sitting together and engaging in a loving conversation, joking with each other, etc. is better than nafl salat.
2. A marriage can be executed by just two words, e.g. a person says the following words in the presence of witnesses: "I give my daughter to you in marriage." The person who is addressed replies: "I accept her in marriage." In so doing, the marriage is valid and both of them are lawful husband and wife. However, if the person has several daughters, the nikah will not be executed by his uttering the words mentioned above. He will have to mention the daughter by name, e.g. he says : "I give my daughter, Qudsiyyah, to you in marriage", and the person replies : "I accept her in marriage."
3. A person says: "Give so-and-so daughter of yours to me in marriage." The father replies: "I give her to you in marriage." In so saying, the nikah will be valid irrespective of whether he says that he accepts or not. (In other words, it is not necessary for the word "accept" to be mentioned).
4. If the daughter is present and the father says: "I give this daughter of mine in marriage to you", and the person replies: "I accept her", the nikah will be valid. It will not be necessary to mention her name. If the girl is not present, it is necessary to mention her name and the name of her father in such a loud tone that all the witnesses are able to hear. If the people do not know the father and there is a strong possibility that by mentioning his name they will still not know whose nikah is being performed, then it will be necessary to mention the name of the grand-father as well. In other words, such identification is necessary whereby those present immediately know whose nikah is being performed.
5. In order for a nikah to be valid, it is also essential for at least two males or one male and two females to be present, to hear the nikah being performed, and to hear the two words (i.e. the offer and the acceptance) being uttered. Only then will the nikah be valid. If two persons sit together in privacy and one says to the other : "I give my daughter to you in marriage" and the other person replies : "I accept your daughter", the nikah will not be valid. Similarly, if the nikah was performed in the presence of one person only, even then the nikah will not be valid.
6. If there are no males present, but only females, the nikah will not be valid even if there are ten females present. Together with two females, one male has to be present.
7. If there are two males but they are not Muslims, the nikah will not be valid. Similarly, if both are Muslims but both or one of them is immature, the nikah will not be valid. Similarly, if there is one male and two females but both or one of the females is immature, the nikah will not be valid.
8. It is preferable to perform the nikah in a large gathering such as after the jumu'ah salat in a jumu'ah musjid or in any other large gathering. This is so that the nikah will be well announced and the people will become aware of the nikah. A nikah should not be performed in secret and privacy. However, if due to some reason many persons are unable to attend, then at least two males or one male and two females who hear the nikah being performed in their very presence should be present.
9. If both the man and woman are mature, they can perform their own nikah. All that they have to do is say the following in the presence of two witnesses: One of them must say: "I am making my nikah with you" and the other must say : "I accept." In so doing, the nikah will be valid.
10. If a person does not make his nikah himself, but asks someone to perform his nikah with someone, or, he mentions the name of the person with whom he wishes his nikah to be performed and this person performs this nikah in the presence of two witnesses - the nikah will be valid. Even if this person rejects or denies this later, the nikah will still be intact. ( By Moulana Ashraf Ali Thanvi RH).