COMMENTARY on 12:31
Mustafa Khattab:

Translation:
When she heard about their gossip,10 she invited them and set a banquet for them. She gave each one a knife, then said ˹to Joseph˺, “Come out before them.” When they saw him, they were so stunned ˹by his beauty˺ that they cut their hands,10 and exclaimed, “Good God! This cannot be human; this must be a noble angel!”
Commentary:
10   lit., ‘their cunning’ because the women themselves were probably interested in Joseph.

 

A. Yusuf Ali:

Translation:
When she heard of their malicious talk, she sent for them and prepared a banquet 1679 for them: she gave each of them a knife: and she said (to Joseph), "Come out before them." When they saw him, they did extol him, and (in their amazement) cut their hands: they said, "(Allah) preserve us! no mortal is this! this is none other than a noble angel!"
Commentary:

1679  When her reputation began to be pulled to pieces with sundry exaggerations and distortions and malicious innuendos, the wife of 'Aziz invited all the ladies in society to a grand banquet. We can imagine them reclining at ease after the manner of fashionable banquets. When dessert was reached and the talk flowed freely about the gossip and scandal which made their hostess interesting, they were just about to cut the fruit with their knives, when, behold! Joseph was brought into their midst. Imagine the consternation which his beauty caused, and the havoc it played with their hearts! "Ah!", thought the wife of ‘Aziz "now is your hypocrisy self-exposed! What about your reproaches to me? You have yourselves so lost your self-control that you have cut your ringers!" (R).

 

Muhammad Asad:

Translation:
Thereupon, when she heard of their malicious talk, she sent for them, and prepared for them a sumptuous repast, 28 and handed each of them a knife and said [to Joseph]: "Come out and show thyself to them!" And when the women saw him, they were greatly amazed at his beauty, 29 and [so flustered were they that] they cut their hands [with their knives], exclaiming, "God save us! This is no mortal man! This is nought but a noble angel!"
Commentary:
28  The expression muttaka'-lit., "a place where one reclines [while eating]", i.e., a "cushioned couch" - seems to have been used here tropically to denote a "luxurious [or "sumptuous"] repast".
29  Lit., "they deemed him [i.e., his beauty] great".