Y'aqub bin Hmyd bin Kasb يعقوب بن حميد بن كاسب المدني · The Chapters on Legal Punishments

the case of a man who had intercourse with the slave woman of his wife was referred to the Messenger of Allah (ﷺ), and he did not stipulate any legal punishment for him.

“I asked Fadalah bin Ubaid about hanging the hand (of the thief) from this neck, and he said: 'It is sunnah. The messenger of Allah (ﷺ) cut off a man's hand then hung it from his neck'''