وَإِنْ كُنْتُنَّ تُرِدْنَ اللَّهَ وَرَسُولَهُ وَالدَّارَ الْآخِرَةَ فَإِنَّ اللَّهَ أَعَدَّ لِلْمُحْسِنَاتِ مِنْكُنَّ أَجْرًا عَظِيمًا ﴿۲۹﴾ يَا نِسَاءَ النَّبِيِّ مَنْ يَأْتِ مِنْكُنَّ بِفَاحِشَةٍ مُبَيِّنَةٍ يُضَاعَفْ لَهَا الْعَذَابُ ضِعْفَيْنِ وَكَانَ ذَلِكَ عَلَى اللَّهِ يَسِيرًا ﴿۳۰﴾

﴾29﴿ Wa in kuntunna turidnal laaha wa Rasoolahoo wad Daaral Aakhirata fa innal laaha a'adda lil muhsinaati min kunna ajjran 'azeemaa
﴾30﴿ Yaa nisaaa'an Nabiyyi mai yaati minkunna bifaa hishatim mubaiyinatiny yudaa'af lahal 'azaabu di'fain wa kaana zaalika 'alal laahi yaseera

﴾29﴿ But if you desire Allah, His Messenger, and the Hereafter, then indeed, Allah has prepared a great reward for the righteous among you
﴾30﴿ O wives of the Prophet (peace and blessings be upon him), whoever among you commits a clear immorality, the punishment for her will be doubled twofold, and that is easy for Allah

[29] This is the second side of the choice: “If you desire Allah and His Messenger” — the meaning of this is being pleased with and obeying both of them. “And the Hereafter” — the meaning of this is Paradise, which is attained through obedience to Allah Almighty and His Messenger. “Among you” — the word min here is explanatory; its meaning includes all the wives of the Prophet. However, it was mentioned for the purpose of warning them. And since this ruling also includes the other women of the Ummah, and the wives of the Prophet ﷺ are only a part of them, for this reason the word min was also mentioned.
[30] This is an address to the wives of the Prophet (May Allah bless him and give him peace) — and also considered the fifth general address to this ummah.
Since they had chosen Allah, His Messenger, and Paradise, now Allah mentions those actions which, if practiced, lead to the pleasure of Allah, His Messenger, and entry into Paradise.
"Mubayyinah" means a sin that is clearly evil — both legally (shar‘an) and rationally (‘aqlan) — with no possibility of it being considered permissible.
"Ḍi‘fayn" — the word ḍi‘f already implies a doubling or multiplying, but using the dual form (twofold) emphasizes repetition and intensity.
It indicates that the higher a person’s status, the more serious their wrongdoing is considered, and therefore their reproach and punishment is also more severe.