The Command to fight Those Who fight Muslims and killing Them wherever They are found

Abu Ja`far Ar-Razi said that Ar-Rabi` bin Anas said that Abu Al-`Aliyah commented on what Allah said:

وَقَـتِلُواْ فِي سَبِيلِ اللَّهِ الَّذِينَ يُقَـتِلُونَكُمْ

As already explained briefly in the opening remarks, the verse 191, that is, وَاقْتُلُوهُمْ حَيْثُ ثَقِفْتُمُوهُمْ وَأَخْرِ‌جُوهُم (And kill them; wherever you find them and drive them out from where they drove you out...), was revealed after the happening at Hudaybiyyah حُدیبیہ at a time when the Holy Prophet ﷺ decided, in accordance with the condition agreed upon in the Peace Treaty of Hudaybiyyah حُدیبیہ ، to embark on a journey to Makkah to perform the qada' قضاء of ` Umrah along with his Companions, something he was stopped from doing a year before by the disbelievers of Makkah. The noble Companions ؓ ، on the eve of this projected journey, had started to worry about the disbelievers who could not be trusted upon in a peace treaty. If they chose to be aggressive, as they did a year before, what option are they going to take? Thereupon, the words used in the present verse gave them the permission to meet the challenge of their aggression and kill them where they find them. And if they could, it was permissible for them to drive the disbelievers out from where they had driven the believers out.

Since Muslims, during their entire Makkan period, were made to stay away from fighting against the disbelievers and were repeatedly asked to forego and forgive, so much so, that the noble Companions were, before the revelation of this verse, under the impression that killing disbelievers was bad, and prohibited. It was to remove this misconception that it was said: وَالْفِتْنَةُ أَشَدُّ مِنَ الْقَتْلِ "And Fitnah فِتْنَہ is more severe than to kill," that is, it is true that to kill someone is a terribly evil act, but more terrible and severe is what the disbelievers of Makkah have done by insisting on their kufr and shirk شرک (infidelity and the associating of others with Allah) and by stopping Muslims from fulfilling their religious obligations, and from performing Hajj and ` Umrah. It is to avoid this greater evil that killing them has been permitted. The word, Fitnah فِتْنَہ in the verse (not translated for want of a perfect equivalent in English) inescapably means kufr کفر and shirk شرک and to prevent Muslims from fulfilling their religious obligations of ` ibadah.(Jassas, Qurtubi and others)