He insults Islam – should he be friends with him? How should he deal with him?
Question

                I have a friend who insults Islam and says bad things to me in Ramadaan. How should I deal with him? He is always with me and is always saying these insulting things.
Praise be to Allah.
      Insulting Allaah or Islam is major kufr which puts a person 
      beyond the pale of Islam. Allaah says (interpretation of the meaning): 
“Say: Was it at Allaah 
    and His Ayaat (proofs, evidences, verses, lessons, signs, revelations, etc.) 
    and His Messenger that you were mocking?”

    66. Make no excuse; you disbelieved after you had 
    believed”

    [al-Tawbah 9:65,66]

    What you have to do is to remind this slanderer and advise 
    him, and warn him that all his good deeds are to no avail, and that if he 
    does not repent, he will meet Allaah when he is guilty of major kufr. 

    Tell him that the punishment that he deserves in this world 
    is execution, because the Prophet  (peace and blessings of Allaah be 
    upon him) said: “Whoever changes his religion, execute him.” Narrated by 
    al-Bukhaari, 3017. 

    Tell him that he must come back to Islam, and that if he 
    comes back and repents, Allaah will accept his repentance. 

    If he responds, then all well and good, but if he does not 
    respond, it is not permissible for you to stay with him when he is insulting 
    Islam. 

    Shaykh Ibn ‘Uthaymeen was asked about the ruling on staying 
    among people who insult Allaah, may He be glorified. 

    He replied: 

    It is not permissible to stay with people who are insulting 
    Allaah, may He be glorified, because Allaah says (interpretation of the 
    meaning): 
“And it has already been 
    revealed to you in the Book (this Qur’aan) that when you hear the Verses of 
    Allaah being denied and mocked at, then sit not with them, until they engage 
    in a talk other than that; (but if you stayed with them) certainly in that 
    case you would be like them. Surely, Allaah will collect the hypocrites and 
    disbelievers all together in Hell”

    [al-Nisa’ 4:140]

    And Allaah is the Source of strength. End quote. 

    Majmoo’ Fataawa al-Shaykh Ibn ‘Uthaymeen, 
    2/question no. 238 

    It should be noted that bad company will bring nothing but 
    evil, so protect yourself against that. The Prophet  (peace and 
    blessings of Allaah be upon him) likened a bad companion to the one who 
    operates the bellows: either he will burn your clothes, or you will notice a 
    foul smell from him. 

    It was narrated from Abu Moosa (may Allaah be pleased with 
    him) that the Prophet  (peace and blessings of Allaah be upon him) said: 
    “The likeness of a good companion and a bad companion is that of one who 
    carries musk and one who works the bellows. With the carrier of musk, either 
    he will give you some or you will buy some from him, or you will notice a 
    good smell from him; as for the one who works the bellows, either he will 
    burn your clothes or you will notice a bad smell from him.” Narrated by 
    al-Bukhaari, 5543; Muslim, 2628. 

    Al-Nawawi (may Allaah have mercy on him) said: 

    In this hadeeth the Prophet  (peace and blessings of 
    Allaah be upon him) likened a good companion to the one who carries musk, 
    and the bad companion to one who works the bellows. It points to the virtue 
    of sitting with righteous, good and honourable people, people of good 
    attitude, awareness, knowledge and manners, and indicates that it is not 
    allowed to sit with evil people and followers of innovation, those who 
    backbite about people or who are foul-mouthed and have nothing better to do, 
    and other blameworthy things. End quote. 

    Sharh Muslim, 16/178 

    In conclusion: You have to advise this person who lives with 
    you, who has fallen into major kufr because of his insulting Islam, and who 
    has committed a major sin by insulting you. If he responds to your advice 
    and mends his ways, then stay with him and help him to discipline himself, 
    but if he does not respond, then there is nothing good for you in remaining 
    friends with him. 

    And Allaah knows best.