My nephew proposed to my daughter. Though I know he is a smoker and he does not observe Salah (Prayers) regularly, I agreed on condition that he quits smoking and observes Salah regularly.
He accepted my conditions and pledged to fulfill them. He brought his father, his mother (Part No. 18; Page No. 410) and his two paternal uncles with him. I informed them of my conditions and called upon them all as witnesses to these conditions. I gave him a week to think about the matter and the conditions I stipulated. A week later, he came and pledged to give up smoking and to establish prayers regularly. In addition, he turned sincerely to Allah (Exalted be He) in repentance. I swore by Allah (Exalted be He) that if he smokes again and breaks him promise, I will not allow him to kiss my head, my nose or any part of my body unless I were in a coma or dead. May Allah grant us all health and peace of mind. I excluded shaking hands from my oath. I helped him with his marriage by giving him a hundred thousand Riyals. Also, I married my daughter to him without Mahr (mandatory gift to a bride from her groom). Later on, the couple had some problems twice, but I asked my daughter to return to her house. A third disagreement arose and she is staying in my house now. I know for certain that he is smoking again and no longer establishes prayers regularly. I expect no worldly return from him; I granted him money to help him with the marriage and as a reward for his repentance and to give up smoking.A - What is the ruling on my oath?B - What is the ruling on my daughter's life with him and asking her to return to him?Please note that my daughter is his second wife and he has children from his first wife, who is still married to him. (Part No. 18; Page No. 411) My daughter has no children from this marriage. I ask your Eminence to guide us to the right decision, may Allah preserve you.
Abandoning Salah (Prayer) out of denial of its obligation is considered Kufr (disbelief) according to Ijma` (consensus of scholars). Similarly, abandoning Salah out of laziness and indifference is regarded as Kufr, as a preponderant opinion by Muslim scholars. It is not permissible for a Muslim to marry his daughter, sister, and so on, to a person who abandons any of the Five Obligatory Prayers. Rather, you should seek to end this marriage by referring to the competent court in your city. As for your oath, as long as you do not break it, there is no sin on you. If you break your oath, you have to offer Kaffarah (expiation) through feeding ten Miskins (poor persons), clothing them, or manumitting a believing slave. If you cannot afford that, you have to observe fasting for three days. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family and his Companions.