Assalaam alaikum, If a woman makes an oath to Allah saying " if i do this i will become a kafir". 1.Is kaffarah necessary if she breaks the oath? 2.If she does not give kaffarah will she become a kafir by simply not giving the kaffarah? JazakAllah

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

What this woman has done is considered a type of swearing by other than Allaah, which is forbidden. If someone takes an oath that he will be a disbeliever or that he will be a Jew or a Christian or that he will be dissociated from Islam, then this is even worse and more deserving of punishment. Ibn ‘Umar narrated that the Prophet said: "He who has to swear, let him swear by Allaah or let him keep silent." [Al-Bukhari and Muslim]

Thaabit ibn Adh-Dhahhaak narrated that the Prophet, sallallaahu ‘alayhi wa sallam, said: "Whoever intentionally swears falsely by a religion other than Islam, then he is what he has said, and whoever kills himself with an iron weapon, will be punished with it in the Fire." [Al-Bukhari and Muslim]

For more benefit, please refer to Fatwa 90806.

This woman does not become a disbeliever by making such an oath, as it came in the context of an oath. Ad-Dardeer said in his commentary on Khaleel in the Maaliki School of jurisprudence: "…Or that he says that he is a Jew or a Christian, or an apostate, or says that he belongs to a religion other than Islam if he did such a thing and he actually did it, then he is not required to do anything; however, it is forbidden for him to do so, but if he did it outside of an oath, then it consists in apostasy even if he was joking." [End quote]

As regards the expiation, a group of scholars are of the view that no expiation is required for this kind of oath because it is very grave and emphatically forbidden, but other scholars are of the view that the expiation is required for it. Therefore, it is better when breaking an oath to expiate for it, in order to be on the safe side, and to seek as much forgiveness and to do as many righteous deeds as possible. For more benefit, please refer to Fatwa 82135.

Allaah Knows best.