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Surah 3. Aal-Imran
Ayah 28
٢٨. لَّا يَتَّخِذِ ٱلْمُؤْمِنُونَ ٱلْكَـٰفِرِينَ أَوْلِيَآءَ مِن دُونِ ٱلْمُؤْمِنِينَ ۖ وَمَن يَفْعَلْ ذَٰلِكَ فَلَيْسَ مِنَ ٱللَّهِ فِى شَىْءٍ إِلَّآ أَن تَتَّقُوا۟ مِنْهُمْ تُقَىٰةً ۗ وَيُحَذِّرُكُمُ ٱللَّهُ نَفْسَهُۥ ۗ وَإِلَى ٱللَّهِ ٱلْمَصِيرُ
28. Let not the believers take the disbelievers as friends instead of the believers, and whoever does that, will never be helped by Allah in any way, unless you indeed fear a danger from them. And Allah warns you against Himself, and to Allah is the final return.
Allah prohibited His believing servants from becoming supporters of the disbelievers, or to take them as comrades with whom they develop friendships, rather than the believers. Allah warned against such behavior when He said,
(And whoever does that, will never be helped by Allah in any way) meaning, whoever commits this act that Allah has prohibited, then Allah will discard him. Similarly, Allah said,
(O you who believe! Take not My enemies and your enemies as friends, showing affection towards them), until,
(And whosoever of you does that, then indeed he has gone astray from the straight path.) ﴿60:1﴾. Allah said,
(O you who believe! Take not for friends disbelievers instead of believers. Do you wish to offer Allah a manifest proof against yourselves) ﴿4:144﴾, and,
(O you who believe! Take not the Jews and the Christians as friends, they are but friends of each other. And whoever befriends them, then surely, he is one of them.) ﴿5:51﴾.
Allah said, after mentioning the fact that the faithful believers gave their support to the faithful believers among the Muhajirin, Ansar and Bedouins,
(And those who disbelieve are allies of one another, (and) if you do not behave the same, there will be Fitnah and oppression on the earth, and a great mischief and corruption.) ﴿8:73﴾.
Allah said next,
(unless you indeed fear a danger from them) meaning, except those believers who in some areas or times fear for their safety from the disbelievers. In this case, such believers are allowed to show friendship to the disbelievers outwardly, but never inwardly. For instance, Al-Bukhari recorded that Abu Ad-Darda' said, "We smile in the face of some people although our hearts curse them.'' Al-Bukhari said that Al-Hasan said, "The Tuqyah is allowed until the Day of Resurrection.'' Allah said,
(And Allah warns you against Himself.) meaning, He warns you against His anger and the severe torment He prepared for those who give their support to His enemies, and those who have enmity with His friends,
(And to Allah is the final return) meaning, the return is to Him and He will reward or punish each person according to their deeds.