Tirmidhi

Explanation:
1:
From this hadith, the virtue of vinegar as a condiment is established, because it is easily available to everyone at a low cost.

Benefits and Issues:

➊ Simplicity in eating and drinking is commendable.

➋ Whatever can be eaten with bread is considered a side dish; it is not necessary that it be something cooked.

➌ Simple food and ordinary side dishes are also blessings from Allah, for which one should be grateful.

➍ Vinegar is also beneficial from a medical perspective; therefore, it should be included in meals.

The term "salan" (curry/condiment) does not refer to any specific thing; rather, anything by which bread becomes moistened or passes easily down the throat—whether it is in the form of broth and liquid, or in a solid form such as meat, egg, etc.—will be called "salan." Vinegar also moistens the bread and, with the help of its flavor, assists in passing it down the throat, and in fact, aids in digestion as well. These are precisely the characteristics of "salan," therefore vinegar is also considered "salan." If someone swears an oath not to use "salan" and then uses vinegar, he will have to offer expiation (kaffarah) for his oath, because his oath has been broken.