The Ruling on Acting on a Dream

Your Eminence! We received this letter from a distressed woman—according to her own words—(S) As'ad al-Asmar. She writes in her letter: I have a son, and during his pregnancy I saw in my dream an old shaykh who said to me: "You will give birth to a son, so name him Yusuf." When he was born, I named him something else because I had forgotten what I saw. She says: "I still imagine him before my eyes now." The boy has reached the age of ten, and since his birth until now he has been ill; he comes out of one illness only to fall into another, and we have not seen him in a state of health. Does what I saw in the dream have any bearing on this? In other words, should I change his name to Yusuf, perhaps Allah will grant him healing by His permission, Glorified and Exalted is He? I ask for your guidance?
Answer: In the name of Allah, the Most Gracious, the Most Merciful. Praise be to Allah, and blessings and peace be upon the Messenger of Allah, and upon his family and his Companions, and upon those who follow his guidance.
As for what follows: This is the dream the questioner saw: an old shaykh ordered her to name her son Yusuf, then she forgot and did not name him Yusuf, and the boy was afflicted with illness up to the present time. She asks: Does this dream have any effect on this, and should she change his name?
This dream has no effect. A dream in sleep is not relied upon, and it does not bind anyone to anything. It may be from Shaytan to cause harm and sadness, especially if she disliked seeing this shaykh, for that is from Shaytan. The Prophet (peace be upon him) said: If one sees something he dislikes, let him spit to his left three times, seek refuge in Allah from Shaytan and from the evil of what he saw three times, then turn over to his other side, for it will not harm him. This is what the dreamer should do: if he sees something that pleases him, he praises Allah and tells those he loves about it; if he sees something he dislikes, he seeks refuge in Allah from Shaytan and from the evil of what he saw three times, spits to his left three times, then turns over to his other side, for it will not harm him, as the Prophet (peace and blessings be upon him) said.
This boy who is ill has a decree from Allah, Glorified and Exalted is He, in his condition. And you, O questioner, are in a good state, if Allah wills. Illness and hardship are among the trials, and trials for the servant bring much good if he is patient, as the Mighty and Majestic said: [al-Baqarah: 155-157]. It came in an authentic hadith from him (peace and blessings be upon him) that he said: So a person is afflicted with things such as illness in himself, or in his son, or in his wife, or in his relatives, or the loss of wealth, or other things he dislikes. He must be patient and seek reward, and say: "Indeed, to Allah we belong and to Him we return. Allah has decreed and what He willed has happened." He is in a state of great good. No trial befalls a servant that he dislikes, whether illness, worry, sadness, or otherwise, not even a thorn, but Allah expiates his sins thereby.
So upon you, O sister in Allah, is patience and seeking reward, and be glad of the good. I ask Allah to grant your son healing and well-being, and to show you in him what pleases you, and to bestow upon him well-being from what has befallen him. You should ask Allah, the Mighty and Majestic, to grant him health and cure from Him, especially at the end of the prayer in prostration in the night prayer. Ask Allah for his healing and well-being. Present him to whichever doctors are available, perhaps Allah will bestow upon him healing and well-being. As for the dream, it has no effect in this matter. Yes.