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Surah 4. An-Nisaa'
Ayah 15 - 16
15 وَٱلَّـٰتِى يَأْتِينَ ٱلْفَـٰحِشَةَ مِن نِّسَآئِكُمْ فَٱسْتَشْهِدُوا۟ عَلَيْهِنَّ أَرْبَعَةً مِّنكُمْ ۖ فَإِن شَهِدُوا۟ فَأَمْسِكُوهُنَّ فِى ٱلْبُيُوتِ حَتَّىٰ يَتَوَفَّىٰهُنَّ ٱلْمَوْتُ أَوْ يَجْعَلَ ٱللَّهُ لَهُنَّ سَبِيلًا
16 وَٱلَّذَانِ يَأْتِيَـٰنِهَا مِنكُمْ فَـَٔاذُوهُمَا ۖ فَإِن تَابَا وَأَصْلَحَا فَأَعْرِضُوا۟ عَنْهُمَآ ۗ إِنَّ ٱللَّهَ كَانَ تَوَّابًا رَّحِيمًا
[15-16] If any of your women be guilty of indecency, call for four witnesses from among yourselves to testify against them: If they give evidence and prove the guilt, then confine them to their houses until death comes to them or Allah opens some other way out for them .And punish the two of you who commit this crime; then if they both repent and reform themselves, leave them alone,for Allah is generous in accepting repentance, and merciful in forgiving sins.26
26In both these verses (15-16j, punishment for fornication was prescribed for the first time in Islam. According to verse 15, the guilty women were to be kept in confinement till further order, and according to verse I G both the male and the female guilty of fornication were to be punished, that is rebuked. disgraced, beaten, etc. Afterwards this punishment was altered by verse 2 of Surah An-Nur (XXIV). Now both the male and the female are to be scourged with one hundred stripes each.
This gradual enforcement of the criminal law was based on sound practical wisdom. At that tithe the Arabs were not accustomed to live under a settled government with a regular system of law and judiciary. Therefore it might have unwise and too much for them, if the Islamic State had imposed on them its complete system of criminal laws all at once. That is why at first the sort of punishment contained in these two verses was enforced acid then gradually stricter punishments were prescribed for fornication. theft, slander, etc., and finally that complete system of law was evolved which was in force during the time of the Holy Prophet and his rightly guided successors.
The seeming difference in these two verses has misled commentator Suddi to the conclusion that verse I S prescribed the punishment for married women and verse I G for unmarried men and women. Obviously, this flimsy commentary is not supported by any sound argument. Likewise, the commentary of Abu Muslim Isfahani that verse 15 is about the un-natural crime between two females and verse I G about the un-natural crime between two males is also wrong. The Qur'an is concerned only with the fundamental principles of law and morality: therefore it only discusses those problems which are confronted in normal life and does not concern itself with the ones that are met with under abnormal circumstances. These latter problems, as they arise, are left for the people to decide according to their insight. That is why, when after the death of the Holy Prophet the case of unnatural crime between two males was brought before the Companions, none of them turned to these verses for its decision.