Our answer to you will consist of three messages in which there is advice: to them (your brothers), to the suitor and to you. This is how we will answer your question. 

Firstly: 

A message to your brothers: 

1 – Allaah has commanded you to look for that which is in the best interests of your sister in both religious and worldly terms, which includes choosing a good husband who is suitable for your sister, and not preventing her from marrying one who is suitable. You know that marriage cannot be done without a wali (guardian), and that one of the most important duties of the wali is to look for a good husband and make a good choice, even if that means the guardian offering his sister or daughter in marriage to righteous people. Marrying your sister to one who is not suitable or preventing a suitable man from proposing marriage to her is a betrayal of the trust with which Islam has entrusted you. 

2 – You should note that the Prophet (peace and blessings of Allaah be upon him) has told you of the qualities to be found in the man who is suitable for your sister, which may be summed up in two characteristics: religious commitment and good character. These two characteristics, in sha Allaah, will guarantee good and happiness for your sister and her children. The one who is religiously committed will take care of her rights and he will do what Allaah has commanded him to do towards her and her children. He will encourage her to do good and obey Allaah, and will warn her against evil and sin. 

His good character will prevent him from mistreating her, and will make him continue to treat her well; if he dislikes one characteristic in her, he will be pleased with another, so he will be patient in putting up with any crookedness in her nature which Allaah has created in her, and if he wants to leave her he will do so in a kind manner and will give her her rights. 

3 – You should note that it is not permissible for you to marry her to a kaafir, and it is not good for an evildoer to marry your sister. Marriage to a kaafir means that the marriage is invalid, and marriage to an evildoer is a betrayal of the trust and a failure to protect her.  

The one who does not pray is not a Muslim. The fact that he is a kaafir is mentioned in the Qur’aan and Sunnah, and that was the consensus of the Sahaabah (may Allaah be pleased with them). The one who prays but neglects prayer in congregation is an evildoer (faasiq). The one who smokes is also an evildoer, as is the one who drinks alcohol, which is the mother of all evils. Such a man should not be married and he cannot be trusted to take care of his wife and protect her honour, and he cannot be trusted to take care of his children. 

Allaah has made you the guardians in charge of arranging your sister’s marriage, and He has enjoined upon you to fulfil the trust and be sincere towards her in the best of ways. This means that you should find out  how religiously committed  the one who proposes marriage to your sister is, and how good his character is. If you find that he does not pray, then do not give your sister in marriage to him, because by not praying he is a kaafir. But you must advise him. If he is careless about praying on time or he does not pray in congregation, or he drinks alcohol, then do not give your sister in marriage to him either, because the trust requires you to marry her to one whose religious commitment and character are good. 

4 –Fear Allaah with regard to your sister, and do not mistreat her. Do not be upset by the delay in her getting married or her remaining single. She is putting up with worries which we do not think that you men could bear. Instead of that you should try to support her and help her to be patient, and you should keep her good company, until she is blessed with a righteous husband and good children who will give her good company.  

Secondly: 

Our message to the suitor: 

1 – Remember that Allaah, may He be exalted, has judged the one who does not pray to be a kaafir. The same is mentioned in the Sunnah, and the companions of the Prophet (peace and blessings of Allaah be upon him) were unanimously agreed upon that. Allaah says (interpretation of the meaning): 

“But if they repent [by rejecting Shirk (polytheism) and accept Islamic Monotheism], perform As-Salaah (Iqaamat-as-Salaah) and give Zakaah, then they are your brethren in religion”

[al-Tawbah 9:11]

It was narrated that Jaabir (may Allaah be pleased with him) said: I heard the Messenger of Allaah (peace and blessings of Allaah be upon him) say: “Between a man and shirk and kufr there stands his giving up prayer.” Narrated by Muslim (82). 

‘Abd-Allaah ibn Shaqeeq said: The companions of the Prophet (peace and blessings of Allaah be upon him) did not think that failing to do any deed counted as kufr, except prayer. Narrated by al-Tirmidhi (2622). If you are not praying, then you must repent from this deed and you have to go back to praying regularly, as Allaah has enjoined you, at the proper times fulfilling the conditions of prayer and doing all the obligatory parts of prayer. 

2 – You should note that neglecting the prayer until the time for it is over is one of the deeds for which Allaah has warned of punishment. Allaah says (interpretation of the meaning): 

“Then, there has succeeded them a posterity who have given up As‑Salaat (the prayers) [i.e. made their Salaat (prayers) to be lost, either by not offering them or by not offering them perfectly or by not offering them in their proper fixed times] and have followed lusts. So they will be thrown in Hell”

[Maryam 19:59] 

“Those who delay their Salaah (prayer from their stated fixed times)”

[al-Maa’oon 107:5]

3 – As for alcohol, how evil it is. Allaah says (interpretation of the meaning): 

“O you who believe! Intoxicants (all kinds of alcoholic drinks), and gambling, and Al‑Ansaab (stone altars for sacrifices to false gods) and Al‑Azlaam (arrows for seeking luck or decision) are an abomination of Shaytaan’s (Satan’s) handiwork. So avoid (strictly all) that (abomination) in order that you may be successful”

[al-Maa’idah 5:90]

And the Messenger of Allaah (peace and blessings of Allaah be upon him) said: “Every intoxicant is khamr and every intoxicant is haraam. Whoever drinks khamr in this world and dies when he is addicted to it and has not repented, will not drink it in the Hereafter.” Agreed upon. 

And he (peace and blessings of Allaah be upon him) said: “Every intoxicant is haraam. Allaah has made a covenant that whoever drinks intoxicants, He will give him to drink of the mud of al-khabaal.” They said: O Messenger of Allaah, what is the mud of al-khabaal? He said: “The sweat of the people of Hell, or the juice of the people of Hell.” Narrated by Muslim (2002). 

And he said: “Khamr is the mother of all evils. Whoever drinks it, his prayers will not be accepted for forty days, and if he dies with that in his stomach he will have died a death of Jaahiliyyah.” Narrated by al-Tabaraani, classed as hasan by al-Albaani. 

4 – You should note that smoking is haraam, and it destroys wealth and the body. Allaah will ask you about your wealth and on what you spent it. If smoking is the cause of your death then you will come under the ruling on one who committed suicide, which is a major sin. 

5 – We appreciate your honouring your parents, especially your mother. We also appreciate your good treatment of other people and your attention to your work. But you must note that your not praying or your shortcomings with regard to prayer, and the fact that you smoke, mean that the guardians must refuse to marry you to their sister, and the woman must refuse to accept you as a husband. We hope that you will review your deeds and make all of them good and righteous, then you will deserve to be the husband of a righteous woman, and you and she can build a righteous household based on the Book of Allaah and the Sunnah of His Prophet (peace and blessings of Allaah be upon him), and form a good and blessed family. 

Thirdly: 

Our message to you:  

1 – We advise you to be patient and adhere steadfastly to the truth, and we do not advise you to compromise on the issue of religious commitment and good character in those who propose to you, even if you remain unmarried for a long time. Women are weak by nature, and a woman may marry a man who commits sins with the aim of guiding him, but many women have failed in that. So do not follow this path which many have followed before you, without succeeding. It is said that a woman follows the way of her husband. 

2 – If your brothers want to insist on your marrying this suitor, then they must understand why you are refusing to marry him, and they should tell him frankly about that, and take a promise from him that he will adhere to the laws of Allaah. That may be done with the knowledge of his family, so as to ensure his seriousness about keeping his promise. There should be a lapse of time to prove whether he is actually keeping his promise, before the marriage contract is completed. 

3 – If we exclude his not praying, the other sins that he is committing do not affect the validity of the marriage contract, but we advise you to do that which is best. If you choose to marry him in spite of all the problems he has, with the hope that he will be guided, that is up to you. Rather we say this so that you will not think that marrying him – in the latter case – is haraam, although we prefer for you to be patient and make du’aa’, so that Allaah will give you a way out and send you a husband who is better than him. 

4 – You should note that married life with one who is religiously committed and of good character is a happy life in which a woman can establish her household in accordance with Qur’aan and Sunnah, and develop herself and raise her children in accordance with that which our Lord loves and is pleased with. But a life with one who commits sin will bring worries and distress and a focus on worldly matters, and a failure to attain the pinnacle of good morals. Sin drags a person to further sin, until his heart becomes blackened and he does not acknowledge anything good or condemn anything bad. The one who is of good character and religiously committed may occasionally do something bad, just as the one who commits sin may occasionally do something good, but marriage, partnership, love and brotherhood can only be based on that which is present and established, not that which is hoped for or impossible. 

Shaykh Muhammad ibn Saalih al-‘Uthaymeen (may Allaah have mercy on him) said: 

The most important characteristics for which a woman should choose a suitor are good character and religious commitment. Wealth and good lineage are secondary matters. The most important thing is that the suitor should be religiously committed and of good character, because the woman will not lose anything with a husband who is religiously committed and of good character. If he keeps her, he will keep her on reasonable terms and if he divorces her he will release her with kindness. Moreover the one who is religiously committed and of good character will be a blessing for her and her children, and she will learn good attitudes and religion from him. But if he is not like that, then she should keep away from him, especially some of those who are negligent about performing prayers or who are known to drink alcohol – Allaah forbid. As for those who do not pray at all, they are kuffaar and it is not permissible for them to marry believing women, and they are not permissible for (believing women) either. What matters is that the believing woman should focus on good character and religious commitment. As for good lineage, if that is present too, then it is better, because the Messenger (peace and blessings of Allaah be upon him) said: “If there comes to you one with whose religious commitment and character you are pleased, then give (your daughter or female relative under your care) in marriage to him.” But if they are socially compatible, that is better.

Fataawa al-Mar’ah al-Muslimah (2/702) 

And he (may Allaah have mercy on him) said: 

If the suitor does not pray in congregation, then he is a faasiq (evildoer) who is disobeying Allaah and His Messenger, and is going against the consensus of the Muslims, which is that praying in congregation is one of the best acts of worship. Shaykh al-Islam Ibn Taymiyah (may Allaah have mercy on him) said in Majmoo’ al-Fataawa (23/222): The scholars are unanimously agreed that it – i.e., praying in congregation – is one of the most emphasized acts of worship, best acts of obedience, and greatest symbols of Islam. End quote. 

But this evil deed does not put him beyond the pale of Islam, so it is permissible for him to marry a Muslim woman, but someone else who adheres more strictly to the religion and  good attitudes is better than him, even if he is less wealthy and of an inferior lineage, based on what is said in the hadeeth: “If there comes to you one with whose religious commitment and character you are pleased, then give (your daughter or female relative under your care) in marriage to him.” They said: O Messenger of Allaah, even if he has some fault? He said: “If there comes to you one with whose religious commitment and character you are pleased, then give (your daughter or female relative under your care) in marriage to him,” three times. Narrated by al-Tirmidhi. And it is narrated in al-Saheehayn and elsewhere from Abu Hurayrah (may Allaah be pleased with him) that the Prophet (peace and blessings of Allaah be upon him) said: “Women may be married for four things: their wealth, their lineage, their beauty and their religious commitment. Choose the one who is religiously-committed, may your hands be rubbed with dust (i.e., may you prosper).”

These two ahaadeeth indicate that the first things that should be sought in both men and women are religious commitment and good character. What the guardian who fears Allaah and takes his responsibility seriously should do is to pay attention to the teaching of the Prophet (peace and blessings of Allaah be upon him), because he will be asked about that on the Day of Resurrection. Allaah says (interpretation of the meaning): 

“And (remember) the Day (Allaah) will call to them, and say: What answer gave you to the Messengers?”

[al-Qasas 28:65] 

“Then surely, We shall question those (people) to whom it (the Book) was sent and verily, We shall question the Messengers.

7. Then surely, We shall narrate unto them (their whole story) with knowledge, and indeed We have not been absent”

[al-A’raaf 7:6-7]

But if the suitor does not pray at all, whether in congregation or alone, then he is a kaafir who is beyond the pale of Islam who must be asked to repent. If he repents and starts to pray, then Allaah will accept his repentance if it is sincerely for the sake of Allaah, otherwise he should be executed as a kaafir and apostate, and he should be buried somewhere other than the Muslim graveyard, without being washed or shrouded or having the funeral prayer offered for him. The evidence that he is a kaafir is to be found in the texts of the Book of Allaah and the Sunnah of the Messenger of Allaah (peace and blessings of Allaah be upon him). – He quoted the evidence for the one who does not pray being a kaafir, then he said: 

As it is clear from the texts of Qur’aan and Sunnah that the one who does not pray is a kaafir whose kufr puts him beyond the pale of Islam, it is not permissible for him to marry a Muslim woman, according to the texts and scholarly consensus. Allaah says (interpretation of the meaning): 

“And do not marry Al-Mushrikaat (idolatresses) till they believe (worship Allaah Alone). And indeed a slave woman who believes is better than a (free) Mushrikah (idolatress), even though she pleases you”

[al-Baqarah 2:221] 

“then if you ascertain that they are true believers send them not back to the disbelievers. They are not lawful (wives) for the disbelievers nor are the disbelievers lawful (husbands) for them”

[al-Mumtahanah 60:10]

The Muslims are unanimously agreed upon what is indicated by these two texts, that it is haraam for a Muslim woman to marry a kaafir. Based on that, if he gives a woman whose guardian he is, whether his daughter or anyone else, in marriage to a man who does not pray, the marriage is not valid and the woman does not become permissible to that man as the result of that marriage contract, because it is a contract which is not in accordance with the command of Allaah and His Messenger. It is narrated from ‘Aa’ishah (may Allaah be pleased with her) that the Prophet (peace and blessings of Allaah be upon him) said: “Whoever does an action that is not in accordance with this matter of ours will have it rejected.” 

So if a marriage is to be annulled because the husband gives up praying, unless he repents and comes back to Islam by praying, so what about marrying someone who is already known not to pray? 

To sum up: with regard to this suitor who does not pray, if he does not pray in congregation then he is a faasiq (evildoer) whose evil deed does not make him a kaafir, and it is permissible to marry him in that case, but one who is religiously committed and of good character is better than him. 

If he does not pray at all, either in congregation or alone, then he is a kaafir and apostate who is beyond the pale of Islam, and it is not permissible for him to marry a Muslim woman under any circumstances, unless he repents sincerely and starts to pray and adhere to the religion of Islam.

Majmoo’ Fataawa al-Shaykh Ibn ‘Uthaymeen (12/question no 31). 

Seek the help of Allaah with patience, prayer and du’aa’, and we ask Allaah to make you steadfast in obeying Him, and to bless you with a righteous husband and good offspring. 

And Allaah knows best.