Commentary on the hadith “Whoever forsakes (his brother) for more than three (days) and dies, will enter Hell”
Question

I read a hadith which says: “Whoever forsakes his brother for more than three days and dies like that, will enter Hell.” Is this hadith authentic, and what is its meaning?
Praise be to Allah.Firstly:
Al-Bukhari, 5727, and Muslim, 2560, narrated that Abu Ayyub al-Ansari (may Allah be pleased with him) said: The Prophet (blessings and peace of Allah be upon him) said: “It is not permissible for a Muslim to forsake his brother for more than three days, each of them turning away from the other when they meet. The better of them is the first to greet the other with salaam.”
Abu Dawud, 4914, and Ahmad, 9092, narrated that Abu Hurayrah (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “It is not permissible for a Muslim to forsake his brother for more than three (days). Whoever forsakes (his brother) for more than three (days) and dies, will enter Hell.”
Al-Hafiz al-`Iraqi (may Allah have mercy on him) said in Takhrij al-Ihya’, p. 688:
It was narrated by Abu Dawud from Abu Hurayrah with an authentic isnad.
An-Nawawi (may Allah have mercy on him) said in Riyad as-Salihin, p. 433:
It was narrated by Abu Dawud with an isnad that meets the conditions stipulated by al-Bukhari and Muslim.
Al-Albani (may Allah have mercy on him) also classed it as authentic in Sahih Abi Dawud.
Secondly:
The purpose of the hadith is to issue a stern warning about forsaking others and disputing. The one who forsakes his brother for more than three days and does not repent to Allah is deserving of punishment by being admitted to Hell, but the matter is subject to the will of Allah: if He wills He will punish him, and if He wills, He will forgive him.
However, in the case of one who regards doing that as permissible, despite knowing that it is prohibited, and does not heed Allah’s prohibition of that, and does not adhere to it, then this is apostasy from the religion of Allah, may He be Glorified and Exalted.
For more information, please see question no. 9924.
Ibn `Allan (may Allah have mercy on him) said:
“Whoever forsakes (his brother) for more than three (days) and dies” persisting in forsaking him and cutting off ties with him, “will enter Hell.” If Allah wills, He will punish him with the sinners among those who affirmed His oneness, or he will enter Hell to abide therein forever, if he regards that as permissible despite knowing that it is prohibited and that there is scholarly consensus on that.
End quote from Dalil al-Falihin, 8/435.
Al-Qari (may Allah have mercy on him) said:
“and dies” means, in that state, without having repented, “will enter Hell.” At-Turibashti (may Allah have mercy on him) said: That is, he will deserve to enter Hell, because the one who falls into sin is like the one who falls into punishment: if Allah wills, He will punish him, and if He wills, He will forgive him. End quote.
(See: `Awn al-Ma`bud, 13/176).
For more information, please see the answers to questions no. 21878 and 65500.
And Allah knows best.