I would like to ask something regarding cursing. Well, there is this story about a man and his mother. They were poor. One day, the man traveled and he became rich. When he returned, his mother welcomed him but he did not admit that she was his mother. He did not admit that she was his mother because he was ashamed with his poor mother. His mother got upset and he was cursed to become a stone, and he became a stone.
This story is meant to make people learn not to mistreat their mother.
So there is this Muslim person. He wanted to paint his house. He wanted to paint it blue. He then cursed himself that if he does not paint the house blue, he will become a Kaffir/non-Muslim. He has no intention of becoming a Kaffir/non-Muslim. He made that cursed because he does not want to become a Kaffir/non-Muslim and so, he will paint the house blue. So my question is, if he does not paint the house blue, will he become a Kaffir/non-Muslim?

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 is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

We have already issued Fatwa 86030 on the ruling of cursing, and Fatwa 82254 on the rights of parents on their children, so please refer to them.

As regards the saying of a person 'If I do not do so and so, I will become a non-Muslim', then this is a very serious statement and is forbidden. Whoever said so is obliged to repent. A person who says 'I am a non-Muslim if I do not do such and such', or 'I am a non-Muslim if I do not do such and such', he has indeed committed a sin and committed something forbidden.

With regard to whether or not such statement renders him a non-Muslim, and whether or not this is considered an oath, the answer is that if he meant by his statement 'If I do not paint…I will become a non-Muslim'; he urged himself to do something but failed to do so, then he does not become a non-Muslim. Imaam Maalik said: 'Whoever says: 'If I do so and so I will become a Jew, or Christian or have nothing to so with Islam', then this is not an oath, but he should seek Allaah's Forgiveness and he will not become a non-Muslim [by this statement].'

Allaah Knows best.