Sahih Muslim 3660
صحيح مسلم#3660SahihIbn 'Umar (Allah be pleased with them) reported that he divorced his wife while she was in her menses. 'Umar (Allah be pleased with him) asked Allah's Apostle (ﷺ) about that, and he said:Command him to take her back until she is pure and then she enters the second menses and then becomes pure. Then either divorce her (finally) or retain her
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 18:9