In the name of Allah, the Most Gracious, the Most Merciful.
Quran: Chapter 18 ‘Qad Aflaha’ ‘Successful indeed are’, Sura: 24 ‘An Nur’ ‘The Light’, Verse: 4-5
Verse 4: And those who accuse chaste women, and produce not four witnesses, flog them with eighty stripes, and reject their testimony forever. They indeed are the Fasiqun, the disobedient.
Verse 5: Except those who repent thereafter and do righteous deeds; for such verily, Allah is Oft-Forgiving, Most-Merciful.
Explanation by Ibne Kathir:
The prescribed punishment for slandering chaste women:
Allah commands in Verse 4: “And those who accuse chaste women, ….” This Ayah states the prescribed punishment for making false accusations against chaste women, i.e., those who are free, adult and chaste.
If the person who is falsely accused is a man, the same punishment of flogging also applies.
If the accuser produces evidence that what he is saying is true, then the punishment does not apply.
Allah said in Verse 4: “…… and produce not four witnesses, flog them with eighty stripes, and reject their testimony forever. They indeed are the rebellious.”
If the accuser cannot prove that what he is saying is true, then three rulings apply to him:
(firstly) that he should be flogged with eighty stripes,
(secondly) that his testimony should be rejected forever, and
(thirdly) that he should be labeled as a rebellious who is not of good character, whether in the sight of Allah or of mankind.
Explaining the Repentance of the one who makes a false accusation:
Then Allah says in Verse 5: “Except those who repent thereafter and do righteous deeds; (for such) verily, Allah is Oft-Forgiving, Most Merciful.”
This exception refers to the second and third rulings mentioned above.
The flogging has been carried out regardless of whether he repents or persists, and after that there is no further punishment, as is agreed among the scholars.
If he repents, then his testimony may be accepted, and he is no longer to be regarded as a rebellious.
This was the view of Sa`id bin Al-Musayyib — the leader of the Tabi`in — and also a group among the Salaf.
Ash-Sha`bi and Ad-Dahhak said, “His testimony cannot be accepted even if he does repent, unless he himself admits that he said something false, in which case his testimony may be accepted.” And Allah knows best.
Explanation by samia2010oct: As I understand Verse 4 is for the protection of the honor of the women. Honor is supreme in the Exalted Eyes of Allah so if a person tries even by the word of mouth to dishonor a woman, he/ she must be flogged eighty stripes if he/ she cannot produce four witnesses against the person they accuse of adultery, consensual sex. ‘Production of witnesses’ is needed for the flogging of the accuser, the person who accuses a chaste person of adultery. This Verse is not for punishing the ‘rape victims’ and this Verse does not apply to ‘rape cases’, where the rapist makes sure that the case remains unknown and the rape is always against the will of the victim. It is Big Sin to accuse a chaste person, especially chaste women, of adultery. For Big Sins, Gunaah e Kabira, there is the punishment of unbearable burning of whole body by Unending Fire. At this point we also remember that there are many sins for which the punishment by Allah starts in this world too and this sin is one of them.