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Surah 47. Muhammad
Ayah 26 - 28
26 ذَٰلِكَ بِأَنَّهُمْ قَالُوا۟ لِلَّذِينَ كَرِهُوا۟ مَا نَزَّلَ ٱللَّهُ سَنُطِيعُكُمْ فِى بَعْضِ ٱلْأَمْرِ ۖ وَٱللَّهُ يَعْلَمُ إِسْرَارَهُمْ
27 فَكَيْفَ إِذَا تَوَفَّتْهُمُ ٱلْمَلَـٰٓئِكَةُ يَضْرِبُونَ وُجُوهَهُمْ وَأَدْبَـٰرَهُمْ
28 ذَٰلِكَ بِأَنَّهُمُ ٱتَّبَعُوا۟ مَآ أَسْخَطَ ٱللَّهَ وَكَرِهُوا۟ رِضْوَٰنَهُۥ فَأَحْبَطَ أَعْمَـٰلَهُمْ
[26-28] That is why they said to those who showed aversion to what Allah had revealed, "We shall obey you in some matters."36 Allah knows their secret affairs too well. Then, how shall it be when the angels take their souls, and take them away, smiting their faces and their backs?37 that made Allah angry, and hated to adopt the way of His pleasure. So, He rendered all their works fruitless.38
36That is, "In spite of professing the Faith and being counted among the Muslims, they went on conspiring secretly with the enemies of Islam and even pledged to support them in certain matters. "
37That is, "In the world they adopted this attitude so that they may safeguard their interests and may protect themselves from the dangers of the conflict between Islam and infidelity, but how will they escape Allah's wrath after death? At that time no device of theirs will prove helpful for them to remain safe from the punishment by the angels. "
This verse also is one of those verses that point to the torment of barzakh (i.e. torment 'of the grave). It clearly shows that the unbelievers and hypocrites start being afflicted with the torment right from the time of death, and this torment is different from the punishment which they will get on Resurrection after their cases will have been decided by Allah. (For further explanation, see An-Nisa': 97: AI-An'am: 93-94; AI-Anfal: 50: An-Nahl: 28, 32; AI-Mu'minun: 99-100; Ya Sin: 26-27 and E.N.'s 22, 23; AI-Mu'min: 4b and E. N. 63) .
38This refers to all those works that they performed as "Muslims." Their Prayers, their fasting, their payments of the zakat, and all other acts of worship and virtue, which in appearance and form are counted among good works. were rendered void, for they failed to adopt the attitude of sincerity and loyalty towards Allah and Islam and the Muslim community even though they professed to be Muslims; but, on the contrary, they went on conspiring with the enemies of Islam for the sake of small worldly gains, and started devising schemes to save themselves from any possible risks as soon as time came for Jihad in the cause of Allah. These verses are absolutely decisive and conclusive in this regard that in the conflict between Islam and un-Islam the faith of the person whose sympathies are not with Islam and the Muslims, or are with disbelief and the disbelievers, cannot at all be reliable, not to speak of any of his works being acceptable before Allah.