Hafiz Muhammad Ameen
(1) This hadith is a detailed explanation of the previous hadith. On this occasion, the leader of the Hajj was indeed Abu Bakr radi Allahu anhu, but the “proclamation of Bara’ah” (disavowal) was the special responsibility of Ali radi Allahu anhu, because in that tribal era, any proclamation regarding a treaty could only be made by a family member of the Prophet sallallahu alayhi wa sallam; otherwise, the polytheists would not consider it credible. Everyone was aware of Ali’s radi Allahu anhu relationship to the Prophet sallallahu alayhi wa sallam, therefore Ali radi Allahu anhu was chosen for this proclamation. Other announcements were made by Abu Bakr radi Allahu anhu himself, so there is no contradiction between the previous hadith and this hadith.
(2) “Four months”: Apparently, it seems that the four months are to be counted from this proclamation, but some researchers have counted four months from the revelation of the verse of Bara’ah, that is, Shawwal, Dhu al-Qa’dah, Dhu al-Hijjah, and Muharram. The subsequent words of the verse: ﴿فَإِذَا انْسَلَخَ الأشْهُرُ الْحُرُمُ…﴾ () support this, and this is the correct view.
(3) From the wording of this hadith, it appears that the Prophet sallallahu alayhi wa sallam set the duration of every treaty as four months, but this is not correct. Either the narrator made a mistake or was excessively brief. Other ahadith clarify that the proclamation was as follows: “Whoever has a treaty with the Messenger of Allah sallallahu alayhi wa sallam, it will remain valid until its appointed term. And whoever does not have a treaty (or whose term is not specified), he is safe for four months.” See: (Jami’ al-Tirmidhi, Chapter: And from Surah al-Tawbah, Hadith: 3092). Also see: (Tafsir Ibn Kathir, Surah al-Tawbah, Ayah: 2, under the verse ﴿فَسِيحُوا فِي الأرْضِ أَرْبَعَةَ أَشْهُرٍ﴾), meaning that after this, there would be general fighting against the polytheists. In any case, it is unlikely that the Messenger of Allah sallallahu alayhi wa sallam would unilaterally terminate any treaty. The Messenger of Allah sallallahu alayhi wa sallam was extremely observant of fulfilling treaties.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 2961