Explanation of the permissible backbiting based on what was mentioned in the previous hadith in the sixth characteristic of the hadith of Abu Hurayrah (may Allah be pleased with him), which is

The Shaykh : The backbiting that is forbidden by the Book and the Sunnah, and which the Messenger (peace be upon him) described in what is well known in Sahih Muslim: , this is backbiting. So mentioning your brother with what he dislikes is sometimes permissible, and it may even be obligatory, as we mentioned earlier. The scholars have a long discussion on this topic. Imam al-Ghazali, in his book al-Ihya, has a specific book among his many books titled "The Condemnation of Backbiting and Talebearing." And Imam al-Shawkani (may Allah have mercy on him) has a specific treatise on this topic. The important point is that the prohibition of backbiting is a matter of consensus, with no room for debate; especially since the topic, with its authentic hadiths, has already been presented to us in this book, al-Targhib wa al-Tarhib. The purpose now is to explain what is permissible of backbiting, from which many people are hesitant, either out of scrupulousness and cold wariness, or out of ignorance of Islam. This type of knowledge is what should be spread and broadcast among people until it becomes known, just as the original ruling on backbiting is known to everyone.
The original ruling on backbiting is prohibition, so I do not think any Muslim is unaware that a Muslim backbiting about another Muslim is forbidden. But the masses are unaware that some backbiting is permissible, and may even be obligatory. Here I am now directing my speech to connect it to the topic of his saying (peace be upon him): . If, for example, a person comes to a Muslim man asking about another; either he wants to partner with him, for example, or he wants to marry from his family, from his daughter, from his sister, and so on. He asks him: What do you know about this man? What do you know about his sister, about his daughter? The custom in such a question is to answer in the known colloquial dialect: "Everyone is good and blessed." And he may know that the one being asked about does not have all the good and all the blessing, but may be the opposite of that; he has all the evil. This one who conceals the truth from this inquirer who is seeking advice claims, "I want to partner with him, for example, with money; is he trustworthy?" And he may have worked with him, tested him, and known him closely and thoroughly, and found that he is not trustworthy, yet he conceals it from him and covers it up for him; claiming that here the general rule of backbiting applies: .