It is permissible to take loans of items which could be replaced, such as dry groceries, eggs, meat, etc. It is not permissible to take loans of items which are difficult to replace (i.e. it is difficult to obtain an exact replica of the item) such as, guavas, oranges, goats, fowls, etc.
At a time when 10 kilos of wheat was being sold for R10, you borrowed 5 kilos. Thereafter, the price of wheat dropped and 20 kilos of wheat began to be sold for R10. You will still have to give 5 kilos and not more. Similarly, if the price rises, you will still have to give 5 kilos. When the person returned the wheat that he had borrowed from you, he gave you wheat of a higher quality. It is permissible to accept this wheat and it is not regarded as interest. However, at the time of borrowing the wheat it is not permissible to say that you will take wheat that is of a higher quality. It should be remembered that the wheat should not be more in weight. If you take wheat that is more in weight than the one that you had given, it will not be permissible. You must weigh the wheat properly and give it. If slightly more is given (as a precaution), it will be overlooked. You borrowed money or some grains on the promise that you will return it within one month or fifteen days and the person accepted this promise. Even then, mentioning this period will not be considered. In fact, it is not permissible to mention any period. If the person who lent the money or grains needs the same and asks for it, or asks for it without even really needing it, you will have to return it.
You borrowed two kilos of wheat, flour or something else. When the person asked for it, you replied: “I do not have any wheat at the moment. In place of that wheat take R2.” The person agreed to take the money instead. In such a case, the money will have to be handed over to the person there and then. If the person goes into the house in order to bring the money and separates from the person, this agreement will become invalid. He will have to repeat the entire agreement with regard to taking the money instead of the wheat. A person borrowed one silver coin whose market value was R5. Thereafter, the market slumped and the value of the same coin dropped to R4. The person does not have to give any additional silver in order to cover up the R1. Instead, he merely has to give the same silver coin back or any other one which is equal to that one in weight. The person cannot say that he is not going to take the silver coin and that he must bring R5 in cash instead. It is the custom in certain homes that one house may borrow five cooked rotis now, and later when they make their rotis, they return them. This is permissible.
