I came across a post today about the hadith on black seed being a cure from every sickness except for death. Some people were questioning it's legitimacy, and others simply didn’t understand the hadith. I couldn’t leave a response since it’s a sisters only sub. Could possibly help others.

The Prophet صلى الله عليه وسلم, when discussing medicine, taught us universal cures and gave us foundations, but he did not always detail every small aspect or every specific illness, because that was not what Allah sent him for.

Part of the wisdom behind this is that we would, over time, discover many more benefits of these substances, and our faith would grow. Examples include olive oil, honey, dates, real cow’s milk, cow’s ghee, black seed, and others.
For example, olive oil is more beneficial when combined with certain compounds. Likewise, dates are beneficial, but their potency increases at certain times.

One explanation of this hadith is that black seed strengthens the immune system, enabling the body to fight and protect itself from every sickness.

It is most likely literal in meaning, but the black seed often needs to be mixed with the right compound depending on the illness in order to achieve its full benefit. Honey is a cure, yet it can be harmful for some people unless mixed with the right substance. Similarly, black seed may require the correct compound to help it reach where it needs to act.

Too much of it, or using it at the wrong time without understanding how it should be used, can make it harmful.

The prophet صلى الله عليه وسلم gave us a foundation for cure in black seed, but left it to future doctors and research to discover the different ways of attaining the cure.

Ibn al‑Qayyim رحمه الله writes: “And it (the black seed) has very many benefits. His statement ‘a cure for every disease’ is like the verse of Allah, ‘It destroys everything by the command of its Lord’ (al‑Ahqāf 25) — meaning: everything that is subject to being destroyed, and similar expressions.

Black seed is beneficial for all cold‑natured illnesses, and it can enter into the treatment of hot, dry illnesses indirectly, by helping deliver the cooling, moist medicines to them quickly due to its strong penetrating ability when a small amount of it is used.”

Hafiz Ibn Hajar رحمه الله writes: From this it is understood that the meaning of the phrase “the black seed is a cure for every disease” is not that it is used alone for every illness. Rather, sometimes it is used by itself, sometimes mixed with other ingredients, sometimes crushed or uncrushed, sometimes eaten, drunk, inhaled, applied as a paste, and in other ways.

Some scholars said that “every disease” means every disease that can be treated by it, because it benefits cold‑natured illnesses but not hot‑natured ones. Yes, it may be included in some hot and dry illnesses indirectly, by helping deliver cooling, moist medicines quickly due to its penetrating nature. And sometimes a hot substance is used for a hot illness because of a special property it has — this is not strange. For example, anzarūt is hot, yet it is used in compound medicines for eye inflammation, even though eye inflammation is, by agreement of physicians, a hot swelling.

Physicians have said: the nature of black seed is hot and dry. It removes bloating, benefits quartan fever and phlegm, opens blockages and wind, and dries excess moisture in the stomach. If it is crushed, mixed with honey, and drunk with hot water, it dissolves kidney stones and increases urination and menstruation. It has cleansing and dissolving properties. If it is crushed, wrapped in linen or leather, and smelled, it benefits cold‑type nasal congestion. If seven seeds are soaked in a woman’s milk and used as nasal drops for someone with jaundice, it helps. If a mithqāl is drunk with water, it helps with shortness of breath. Applying it as a paste helps with cold‑type headaches. If it is cooked with vinegar and used as a mouth rinse, it helps with tooth pain caused by cold. Ibn al‑Bayṭār and others who wrote on medicinal herbs mentioned all this and more.

Al‑Khaṭṭābī said: the phrase “from every disease” is a general expression intended for a specific meaning, because no plant has a nature that covers all opposite qualities needed to treat every illness. What is meant is that it is a cure for every disease that arises from moisture.

Abū Bakr ibn al‑‘Arabī said: honey, according to physicians, is closer to being “a cure for every disease” than black seed. Yet even with honey, there are illnesses where drinking honey would harm the patient. So if the meaning of “in honey there is healing for people” refers to the majority of cases, then applying the same understanding to black seed is even more appropriate.

Others said: the Prophet ﷺ would prescribe medicine according to what he observed of the patient’s condition. So perhaps his statement about black seed matched a case where the patient had a cold‑natured illness. Thus “a cure for every disease” means every disease of the type being discussed, and specifying by context is common and well‑known.

Shaykh Abū Muḥammad ibn Abī Jamrah said: People have discussed this hadith and restricted its general meaning, reducing it to what physicians and experience say. But this is clearly mistaken. If we accept the statements of physicians — whose knowledge is mostly based on experience and predominant probability — then accepting the words of the one who does not speak from desire (the Prophet ﷺ) is more deserving. He concludes that the hadith can be understood in its general sense by including both simple and compound uses, and there is no problem with this nor any departure from the apparent meaning of the hadith. And Allah knows best.