He divorced his wife while she was in menses during the time of the Messenger of Allah (PBUH), so 'Umar ibn Al-Khattab asked the Messenger of Allah (PBUH) about that, and the Messenger of Allah (PBUH) said: Let him take her back, then let him keep her until she becomes clean, then she menstruates again, then she becomes clean, then if he wants, he can keep her after that, and if he wants, he can divorce her before he touches her [having a sexual intercourse]. That is the waiting period that Allah has prescribed for divorcing a woman.