Bulugh al-Maram #1397

Abu Hurairah (RAA) narrated, 'I heard the Messenger of Allah (ﷺ) say, "When the slave-woman of one of you commits adultery and she is proven guilty (through witnesses or confession), he should flog her as prescribed (for the slave woman), but he should not admonish her. If she does this again, then she should be flogged again but he should not admonish her. If she commits it for the third time, and she is proven guilty, then he must sell her even if it was for a rope of hair." Agreed upon, and the wording is from Muslim.