After the death of his 1st wife, Kadija, the widower Mohammed married Sauda, herself also a widow. Mohammed ended up marring several other wives (the total number of them varies depending on the source), all younger than Sauda. When that happened, Mohammed wanted to divorce Sauda because she was too old and unattractive. Sauda asked Mohammed not to divorce her. In exchange to remain married to Mohammed, at least just nominally she gave away her day (to sleep with Mohammed) to Aisha (Mohammed's child-wife) who then would sleep with Mohammed twice during his rotation among his wives.
What is the problem with that?
1. Mohammed is the example to the nation of Islam.
2. Mohammed set the precedent that a man can divorce a wife whenever he feels his wife has certain defects such as old age or lack of sex-appeal.
3. A woman has no such right.
4. Not to mention that the whole account is just perverted.
Of the above verse Ibn Kathir said:
To get a fuller picture of the above incident let us look at what the commentators said about Q. 4:128.
The author of a standard text book on Islamic law wrote: