Narrated from Sayyiduna Ka'b bin Malik (may Allah be pleased with him) that a man came to the Noble Prophet (peace and blessings be upon him). The Prophet (peace and blessings be upon him) asked him: "How long have you had a fever? It is an increase of heat between the skin and flesh." He replied: "It is such an affliction that I have never suffered from it." The Prophet (peace and blessings be upon him) said: "The example of a believer is like that of a soft, delicate, and fresh crop which is sometimes red and sometimes yellow."

Mu’adh narrates that he came to visit Sayyiduna Abu Darda’ (may Allah be pleased with him), and when he greeted him with salam, he (Abu Darda’) said: Remain with health, not with illness, and he supplicated this three times. Then he said: I heard the Messenger of Allah (peace and blessings be upon him) say: A Muslim remains afflicted with fever and headaches and similar illnesses, while he has sins as great as Mount Uhud, but because of these illnesses, his sins fall away from him such that not even the weight of a mustard seed of sin remains upon him.

Sayyiduna Abu Umamah narrates that the Messenger of Allah, peace and blessings be upon him, said: Fever is the bellows of Hell; for any believer who falls ill, it will be in exchange for his portion of Hell.

It is narrated from Sayyiduna Abu Hurairah, may Allah be pleased with him, that the Messenger of Allah, peace and blessings be upon him, went to visit a sick person who had a fever. The Prophet, peace and blessings be upon him, said to him: Rejoice, for Allah Almighty says: (This fever) is My fire, which I impose upon My believing servant in this world so that it may become a substitute for the punishment of the fire in the Hereafter.

It is narrated from Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both), he says: Fever sought permission to come to the Prophet Muhammad (peace and blessings be upon him). The Prophet (peace and blessings be upon him) said: Who is this? It said: I am Umm Miladim (Mother of Heat). The Prophet (peace and blessings be upon him) ordered that it be transferred to the people of Quba. So they were afflicted with it in such abundance that only Allah knows its extent. Those people came to the Prophet (peace and blessings be upon him) complaining about it. The Prophet (peace and blessings be upon him) said: What do you want? If you want me to pray to Allah to remove it from you, then fine; and if you want it to be a purifier for you, (then let it remain with you). They said: O Messenger of Allah! Does it purify from sins? The Prophet (peace and blessings be upon him) said: Yes. They said: Then let it remain.

It is narrated from Sayyiduna Abu Hurairah (may Allah be pleased with him) that a woman, who used to suffer from epileptic fits, came to the Noble Prophet (peace and blessings be upon him) and said: O Messenger of Allah! Please supplicate to Allah Almighty that He grants me healing. The Prophet (peace and blessings be upon him) said: If you wish, I will supplicate to Allah Almighty for your healing, and if you wish, you may be patient and in return there will be no reckoning upon you. She said: Yes, that is fine, I will be patient and in return there will be no reckoning upon me.

Ata bin Abi Rabah says: Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said to me: Shall I show you a woman of Paradise? I said: Yes, why not. He said: This black woman—she came to the Prophet (peace and blessings be upon him) and said: I have epileptic fits and because of this I become uncovered, so please pray to Allah Almighty for me. The Prophet (peace and blessings be upon him) said: If you wish, be patient and Paradise will be yours, and if you wish, I will pray to Allah Almighty for your cure. She said: I will be patient, but please pray to Allah Almighty that I do not become uncovered. So the Prophet (peace and blessings be upon him) prayed for her in this regard.

It is narrated from Sayyiduna Zayd bin Arqam (may Allah be pleased with him), he says: My eye became diseased and the Noble Prophet (peace and blessings be upon him) came to visit me for my care. When I recovered and went outside, the Messenger of Allah (peace and blessings be upon him) said to me: If your eye disease had remained, what would you have done? I said: If my eye disease had remained, I would have been patient and intended to seek reward. He (peace and blessings be upon him) said: If you had been patient and intended to seek reward in the case of this disease remaining, you would have met Allah in such a state that there would be no sin upon you. The words of the narrator Isma'il are: Then if you had been patient and intended to seek reward, Allah would have made Paradise obligatory for you.

It is narrated from Sayyiduna Anas (may Allah be pleased with him), he says: I and the Noble Prophet (peace and blessings be upon him) went to visit Sayyiduna Zayd bin Arqam (may Allah be pleased with him) to inquire about his health, his eye was diseased. The Prophet (peace and blessings be upon him) said: O Zayd! If the illness of your eyes were to remain?... Then words similar to the above-mentioned narration were reported.

Narrated from Sayyiduna Anas (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Your Lord, the Exalted, has said: When I take away the eyesight of someone and he remains patient seeking reward, then his reward will be Paradise.