Tafsir
Tafsir of At-Tawbah 4
إِلَّا ٱلَّذِينَ عَـٰهَدتُّم مِّنَ ٱلْمُشْرِكِينَ ثُمَّ لَمْ يَنقُصُوكُمْ شَيْـًٔا وَلَمْ يُظَـٰهِرُوا۟ عَلَيْكُمْ أَحَدًا فَأَتِمُّوٓا۟ إِلَيْهِمْ عَهْدَهُمْ إِلَىٰ مُدَّتِهِمْ ۚ إِنَّ ٱللَّهَ يُحِبُّ ٱلْمُتَّقِينَ
Excepted are those with whom you made a treaty among the polytheists and then they have not been deficient toward you in anything or supported anyone against you; so complete for them their treaty until their term [has ended]. Indeed, Allāh loves the righteous [who fear Him].
Tafsir Ibn Kathir (abridged)
Hafiz Ibn Kathir · English
Existing Peace Treaties remained valid until the End of Their Term
This is an exception regulating the longest extent of time for those who have a general treaty - with out time mentioned - to four months. They would have four months to travel the lands in search of sanctuary for themselves wherever they wish. Those whose treaty mentioned a specifec limited term, then the longest it would extend was to the point of its agreed upon termination date. Hadiths in this regard preceeded. So anyone who had a treaty with Allah's Messenger ﷺ, it lasted until its specific termination date. However, those in this category were required to refrain from breaking the terms of the agreement with Muslims and from helping non-Muslims against Muslims. This is the type whose peace agreement with Muslims was carried out to its end. Allah encouraged honoring such peace treaties, saying,
إِنَّ اللَّهَ يُحِبُّ الْمُتَّقِينَ
(Surely, Allah loves those who have Taqwa) 9:4, who keep their promises.
Tafsir text: quran.com and the House of Islam API. · At-Tawbah 9:4