There is not to be upon the Prophet any discomfort concerning that (33:38)

﴿مَّا كَانَ عَلَى النَّبِيِّ مِنْ حَرَجٍ فِيمَا فَرَضَ اللَّهُ لَهُ ۖ سُنَّةَ اللَّهِ فِي الَّذِينَ خَلَوْا مِن قَبْلُ ۚ وَكَانَ أَمْرُ اللَّهِ قَدَرًا مَّقْدُورًا﴾
[ الأحزاب: 38]

33:38 There is not to be upon the Prophet any discomfort concerning that which Allah has imposed upon him. [This is] the established way of Allah with those [prophets] who have passed on before. And ever is the command of Allah a destiny decreed.

There is no sin or oppression on the Prophet ( peace be upon him ) in his marriage to the wife of his adopted son which Allah made permissible for him.
In fact, in doing so, he is following in the way of the Prophets before him; he is not any different to the messengers in that regard.
The Prophet had no choice in the completion of this marriage and nullifying of adoption that Allah decreed; it was a decree which was to pass, there was no one who could overturn it.

There is no blame on the Prophet (SAW) in that which Allah has made legal for him. That has been Allah's Way with those who have passed away of (the Prophets of) old. And the Command of Allah is a decree determined.

phonetic Transliteration

Ma kana AAala alnnabiyyi min harajin feema farada Allahu lahu sunnata Allahi fee allatheena khalaw min qablu wakana amru Allahi qadaran maqdooran

Abdullah Yusuf Ali - Translation

There can be no difficulty to the Prophet in what Allah has indicated to him as a duty. It was the practice (approved) of Allah amongst those of old that have passed away. And the command of Allah is a decree determined.

Safi-ur-Rahman al-Mubarakpuri

There is no blame on the Prophet in that which Allah has made legal for him. That has been Allah's way with those who have passed away of old. And the command of Allah is a decree determined.

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