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Surah 9. Al-Tawba
Ayah 5 - 6
٥. فَإِذَا ٱنسَلَخَ ٱلْأَشْهُرُ ٱلْحُرُمُ فَٱقْتُلُوا۟ ٱلْمُشْرِكِينَ حَيْثُ وَجَدتُّمُوهُمْ وَخُذُوهُمْ وَٱحْصُرُوهُمْ وَٱقْعُدُوا۟ لَهُمْ كُلَّ مَرْصَدٍ ۚ فَإِن تَابُوا۟ وَأَقَامُوا۟ ٱلصَّلَوٰةَ وَءَاتَوُا۟ ٱلزَّكَوٰةَ فَخَلُّوا۟ سَبِيلَهُمْ ۚ إِنَّ ٱللَّهَ غَفُورٌ رَّحِيمٌ
٦. وَإِنْ أَحَدٌ مِّنَ ٱلْمُشْرِكِينَ ٱسْتَجَارَكَ فَأَجِرْهُ حَتَّىٰ يَسْمَعَ كَلَـٰمَ ٱللَّهِ ثُمَّ أَبْلِغْهُ مَأْمَنَهُۥ ۚ ذَٰلِكَ بِأَنَّهُمْ قَوْمٌ لَّا يَعْلَمُونَ
[5-6] Then, when the months made unlawful6 for fighting expire, kill the mushriks wherever you find them, and seize them, and besiege them, and lie in wait for them at every place of ambush. But if they repent, and establish Salat and pay the Zakat dues, then let them go their way:7 for Allah is Forgiving and Compassionate. And if any of the mushriks requests you for protection so that he may come to you (to hear the Word of Allah), give him protection till he hears the Word of Allah; then convey him. to the place of his safety: this should be done because these people do not know the Truth.8
6Here "the months made unlawful" are not those four months during which war is forbidden for the sake of Haj and `Umrah but the four months that were made unlawful for the Muslims to make any attack on the mushriks, who were granted respite by v. 2.
7That is, "Mere repentance from disbelief and shirk will not end the matter. but they shall have to perform the prescribed prayer and pay Zakat dues. Without these it will not be considered that they had given up disbelief and embraced Islam. " Hadrat Abu Bakr based his decision on this verse in the case of the apostates, after the death of the Holy Prophet, who argued that they were not the rejecters of Islam, because they offered Salat, even though they had refused to pay the Zakat dues. This argument roused doubts in the minds of the Companions in general that they had no right to fight with such people as these. But Hadrat Abu Bakr removed their doubts, saying, "Verse 5 enjoins us to let those people go their way who fulfill all the three conditions- repentance from shirk, the establishment of Salat and the payment of Zakat. We cannot forbear them, because they do not fulfill one of these three conditions."
8That is, "if during a fight, an enemy makes a request that he should be given an opportunity to understand Islam, the Muslims should give him a surety of protection and allow him to visit them. They should then present Islam before him in order to make him understand it. If, after this, he does not embrace Islam, they should convey him safely to his place" . Such a person who comes to Dar-ul-Islam under the above mentioned protection is called musta'min in the Islamic Code.