Negation of faith in the Hadith “No one of you believes until he loves for his brother what he loves for himself”
Question

In the hadith “No one of you believes until he loves for his brother what he loves for himself,” is what is meant that the person is a disbeliever – even if he believes in the Qur’an and Sunnah – until he loves his brothers? Or is what is meant that his faith is not complete? I hope you can explain.
Praise be to Allah.With regard to the negation of faith in Quranic verses and Hadiths, sometimes what is meant is that the person is not a believer at all, so the person is a disbeliever, and sometimes what is meant is that the person does not have complete faith; thus he is basically a believer, so he is not a disbeliever, but he is lacking in faith.
The Hadith asked about is of the second type.
An-Nawawi (may Allah have mercy on him) said:
What it means is that his faith is not complete, otherwise one who has not attained this characteristic is still basically a believer. (End quote from Sharh Muslim, 2/16)
Al-Qurtubi (may Allah have mercy on him) said:
What is meant is that his faith has not reached the perfect level until, in addition to his being a Muslim, people are safe from his harm, he wants good for them and he is sincere towards all of them in his dealings with them. (End quote from Al-Mufhim lima Ashkala min Talkhis Sahih Muslim, 1/224).
He also said:
That is: his faith is not complete, because the one who deceives a Muslim and is not sincere towards him is committing a major sin, but he does not become a disbeliever as a result, as we have explained more than once.
Based on that, what the Hadith means is that the one who is described as having perfect faith is the one who is sincere in his dealings with people, so he wants for them what he wants for himself and dislikes for them what he dislikes for himself. (End quote from Al-Mufhim, 1/227).
What indicates that what is meant by the negation of faith in this Hadith is negation of complete faith is the fact that the version of this Hadith narrated by Ibn Hibban says: “No one can attain true faith until he loves for people what he loves for himself of good.” (Al-Albani classed it as authentic in Sahih At-Targhib, 1780).
Al-Hafidh Ibn Hajar (may Allah have mercy on him) said:
What is meant by the negation of faith is that the person has not attained complete faith…
Ibn Hibban stated – based on a report of Ibn Abu `Adiy from Husayn Al-Mu`allim – that in the Hadith “No one can attain true faith,” what is meant by “true faith” is complete faith, which means that the one who does not attain this characteristic does not become a disbeliever. (End quote from Fat-h Al-Bari, 1/57).
Ibn Rajab (may Allah have mercy on him) said:
“No one can attain true faith until he loves for people what he loves for himself of good” – this version explains the meaning of the version that is narrated by al-Bukhari and Muslim, and demonstrates that what is meant by the negation of faith is that the individual has not attained true or ultimate faith. Faith is often negated because it is lacking some of its essential or obligatory parts, as when the Prophet (blessings and peace of Allah be upon him) said: “No adulterer is a believer at the time when he is committing adultery; no thief is a believer at the time when he is stealing; no drinker of wine is a believer at the time when he is drinking it” and “He does not believe, whose neighbour is not safe from his evil conduct.” (End quote from Jami` Al-`Ulum wal-Hikam, 120)
What is meant by the negation of faith here is the lack of complete faith that is obligatory. So the one who does not love for his brother what he loves for himself is falling short in the faith that is required of him and is committing something that is prohibited, for which he deserves punishment.
Al-Hafidh Ibn Rajab (may Allah have mercy on him) said:
When the Prophet (blessings and peace of Allah be upon him) said that the one who does not love for his brother what he loves for himself does not truly believe, this indicates that this is one of the characteristics of faith and, in fact, is one of the obligations thereof, for faith cannot be negated unless one of its obligations is not being met, as the Prophet (blessings and peace of Allah be upon him) said elsewhere: “No adulterer is a believer at the time when he is committing adultery…” Rather a man can only love for his brother what he loves for himself when he is free of envy, rancour, deceit and resentment, and that is something that is obligatory. (End quote from Fat-h Al-Bari, 1/41).
And Allah knows best.