Suhayl bin `Amr came.'' Ma`mar said that Ayyub said to him that `Ikrimah said, "When Suhayl bin `Amr came, the Prophet said,
«قَدْ سَهُلَ لَكُمْ مِنْ أَمْرِكُم»
(Now the matter has become easy for you.)''
Ma`mar said that Az-Zuhri narrated, "When Suhayl bin `Amr came, he said to the Prophet , `Please conclude a peace treaty with us.'
So, the Prophet called `Ali bin Abi Talib and said to him,
«اكْتُبْ بِسْمِ اللَّهِ الرَّحْمنِ الرَّحِيم»
(Write: In the Name of Allah, Ar-Rahman, Ar-Rahim.)
Suhayl bin `Amr said, `As for Ar-Rahman, by Allah, I do not know what it means. So write: By Your Name, O Allah, as you used to write previously.'
The Muslims said, `By Allah, we will not write except: By the Name of Allah, Ar-Rahman, Ar-Rahim.'
The Prophet said,
«اكْتُبْ بِاسْمِكَ اللْهُم»
(Write: "In Your Name O Allah.'')
Then he dictated,
«هذَا مَا قَاضَى عَلَيْهِ مُحَمَّدٌ رَسُولُ الله»
(This is a peace treaty, which Muhammad, Allah's Messenger has concluded.)
Suhayl said, `By Allah, if we knew that you are Allah's Messenger, we would not prevent you from visiting the Ka`bah, and would not fight with you.
So, write: Muhammad bin `Abdullah.' The Prophet said to him,
«وَاللهِ إِنِّي لَرَسُولُ اللهِ وَإِنْ كَذَّبْتُمُونِي، اكْتُبْ مُحَمَّدُ بْنُ عَبْدِالله»
(By Allah! I am the Messenger of Allah even if your people do not believe me. Write: "Muhammad bin `Abdullah.'')''
Az-Zuhri continued, "The Prophet accepted all those things, since he had already said that he would accept everything they would demand if it respects the ordinance of Allah, the Exalted.''
The Hadith continues, "The Prophet said to Suhayl,
«عَلَى أَنْ تُخَلُّوا بَيْنَنَا وَبَيْنَ الْبَيْتِ فَنَطُوفَ بِه»
(On the condition that you allow us to visit the House so that we may perform Tawaf around it.)
Suhayl said, `By Allah, we will not, so as not to give the Arabs a chance to say that we have yielded to your pressure, but we will allow you next year.'
So, the Prophet had that written. Then Suhayl said, `We also stipulate that you should return to us whoever comes to you from us, even if he embraced your religion.'
The Muslims protested, `Glorified be Allah! How can a person be returned to the idolators after he has become a Muslim'
While they were in this state Abu Jandal bin (son of) Suhayl bin `Amr came from the valley of Makkah staggering with his chains and fell down among the Muslims.
Suhayl said, `O Muhammad! This is the very first term with which we make peace with you, that is, you shall return Abu Jandal to me.'
The Prophet said,
«إِنَّا لَمْ نَقْضِ الْكِتَابَ بَعْد»
(The peace treaty has not been written yet.)
Suhayl said, `Then by Allah, I will never conduct peace with you.'
The Prophet said,
«فَأَجِزْهُ لِي»
(Release him to me,)
and Suhayl responded, `I will never allow you to keep him.' The Prophet said,
«بَلَى فَافْعَل»
(Yes, do.)He said, `I will not.' Mikraz said, `We allow you (to keep him).'
Abu Jandal said, `O, Muslims! Will I be returned to the idolators although I have come as a Muslim Don't you see how much I have suffered' Abu Jandal had been tortured severely for the cause of Allah, the Exalted and Most Honored.
Tafsir ibn Kathir - Surah Al Fath;
http://tafsir.com/default.asp?sid=48&tid=49543
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