We praise Allaah for having blessed your friend and guided him to Islam, as we ask Allaah to make him steadfast in adhering to it until death. He has succeeded in attaining the greatest achievement in life, which is coming forth from the darkness of kufr and shirk to the light of Islam and guidance, and the worship of Allaah alone with no partner or associate. Whatever blameworthy former customs are left, it will be easy for him to give them up in sha Allaah, if he seeks the help of Allaah, because whoever gives up the religion that he grew up in and enters the true religion, it will become easy for him to give up the habits that he was accustomed to during his jaahiliyyah. The secret habit (i.e. masturbation) is a disease which harms the one who does it. See question no. 329, 12277.
So he has to give up this bad habit and follow the advice of the Prophet (peace and blessings of Allaah be upon him), who said, “ Young men, whoever among you can afford to get married, let him do so, for it is more effective in lowering one’s gaze and guarding one’s chastity. Whoever cannot afford that, then let him fast, for it will be a shield for him.” (Narrated by al-Bukhaari, 5065; Muslim, 1400).
With regard to his question about having sex with his fiancée – if what he means by fiancée is the woman with whom he has made a marriage contract according to sharee’ah, then whatever sexual activities he does with her are correct, good and halaal. But if he is referring to a woman to whom he has proposed marriage but has not yet made a marriage contract, then what they are doing is haraam and is a kind of zina (fornication or adultery) and evil action, and both of them have exposed themselves to the wrath and punishment of Allaah.
The fact that he is financially unable to get married does not justify doing the things that he has done with his fiancée, if he had not made a proper marriage contract with her. It should be noted that the fiancée is considered to be a stranger (non-mahram) to the fiancé, like any other non-mahram woman, so it is not permissible for him to be alone with her, or for her to masturbate him with her hand, or for him to kiss her, or for him to speak to her unless that is for a specific purpose and from behind a screen and without any feelings of desire. See question no. 8994.
The solution in this case is for him to do the marriage contract with her, because if he does the marriage contract with a woman it is then permissible for him to do everything with her, as she has now become his wife, even if the wedding party has not yet taken place. See question no. 13886.
It is also permissible for a husband to be masturbated by his wife’s hand. See question no. 826.
If he is not able to get married, then he has to be patient, as stated above. And Allaah is the Source of strength.
Sheikh Muhammed Salih Al-Munajjid