Whoever repents to Allah before the death rattle, Allah accepts his repentance

It is narrated from Sayyiduna Abu Dharr al-Ghifari (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Indeed, Allah Almighty forgives His servant as long as the 'barrier' has not come about." It was said: O Messenger of Allah (peace and blessings be upon him), what is the barrier? He (peace and blessings be upon him) said: "That a person dies while he is a polytheist."
This hadith has a sahih (authentic) chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.

Abd al-Rahman bin al-Baylamani says: I heard a man from among the Companions of the Messenger of Allah (peace and blessings be upon him) say: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents to Allah even one day before he dies, Allah will accept his repentance." He said: Then I mentioned this to another Companion of the Messenger of Allah (peace and blessings be upon him), and he asked: Did you hear this yourself? I said: Yes. He said: I bear witness that I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents half a day before he dies, Allah will accept his repentance." The narrator says: Then I mentioned this to yet another Companion of the Messenger of Allah (peace and blessings be upon him), and he asked: Did you hear this? I said: Yes. He said: I bear witness that I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents a forenoon's span (dahwah) before he dies, Allah will accept his repentance." The narrator says: Then I mentioned this to yet another Companion of the Messenger of Allah (peace and blessings be upon him), and he asked: Did you hear this? I said: Yes. He said: I bear witness that I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents before the gurgling (the death rattle) begins, Allah will accept his repentance."

It is narrated from one of the Companions of the Messenger of Allah (peace and blessings be upon him) that he heard the Messenger of Allah (peace and blessings be upon him) say: "By the One in whose Hand is my soul! Any person who repents one day before he dies, Allah will certainly accept his repentance." The narrator says: Then I told this to (another) Companion of the Prophet (peace and blessings be upon him), and he too narrated it in full, exactly like the hadith of Hisham.

It is narrated from Sufyan al-Thawri (may Allah have mercy on him) that he wrote to Abd al-Rahman bin al-Baylamani asking him about a hadith he narrated from his father, and he wrote back: His father told him that he sat in a gathering of a group of the Companions of the Messenger of Allah (peace and blessings be upon him), and one of them said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents to Allah a year before his death, Allah will accept his repentance." At this another one asked: Did you hear this yourself from the Messenger of Allah (peace and blessings be upon him)? He said: Yes. He said: I too have heard it. Then another said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents to Allah, the Mighty and Majestic, one day before his death, Allah will accept his repentance." Another asked: Did you hear this yourself from the Messenger of Allah (peace and blessings be upon him)? He said: Yes. He said: I too have heard it. Then another said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents to Allah, the Mighty and Majestic, one hour before his death, Allah will accept his repentance." Another asked: Did you hear this yourself from the Messenger of Allah (peace and blessings be upon him)? He said: Yes. He said: I too have heard it. Then another said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever repents before the gurgling (the death rattle) begins, Allah will accept his repentance."
Although Sufyan bin Sa'id is a greater hafiz of hadith than al-Darawardi and Hisham bin Sa'd, he did not mention in this hadith that he heard it directly from Ibn al-Baylamani or from Zayd bin Aslam; rather, he mentioned it by way of permission (ijazah) and correspondence. Therefore, in this matter the word of those who narrated it with the chain "Zayd bin Aslam from Ibn al-Baylamani from a man among the Companions of the Prophet (peace and blessings be upon him)" is more reliable. And Abdullah bin Nafi' al-Madani, in his narration from Hisham bin Sa'd, made the name of this Companion clear: he is Sayyiduna Abdullah bin Amr bin al-As (may Allah be pleased with them both).

It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever repents a year before his death, his repentance will be accepted," until he (peace and blessings be upon him) said: "a month before," until he said: "a week before," until he said: "a day before," until he said: "an hour before," until he (peace and blessings be upon him) said: "as long before as the interval between two milkings of a she-camel (that is, a brief moment, his repentance will be accepted)." The narrator says: I said: Subhanallah! Has Allah, the Mighty and Majestic, not said: "And repentance is not (accepted) for those who keep doing evil deeds until, when death comes to one of them, he says: Now I repent" [Surah al-Nisa: 18]? Sayyiduna Abdullah (may Allah be pleased with him) said: I am only narrating to you what I heard from the Messenger of Allah (peace and blessings be upon him).