Sahih al-Bukhari Book 68, Hadith 1
that he had divorced his wife while she was menstruating during the lifetime of Allah's Messenger (ﷺ) .
`Umar bin Al-Khattab asked Allah's Messenger (ﷺ) about that. Allah's Messenger (ﷺ) said, "Order him (your son) to
take her back and keep her till she is clean and then to wait till she gets her next period and becomes
clean again, whereupon, if he wishes to keep her, he can do so, and if he wishes to divorce her he can
divorce her before having sexual intercourse with her; and that is the prescribed period which Allah
has fixed for the women meant to be divorced."
Abu Bakr admonished me and poked me with his hands in the flank, and nothing stopped me from moving at that time except the position of Allah's Messenger (ﷺ) whose head was on my thigh.
Ibn `Umar said: "I divorced my wife while she was menstruating. `Umar mentioned that to the Prophet . The Prophet (ﷺ) said, (to my father), "Let your son take her back." I asked (Ibn `Umar), "Is such a divorce counted (i.e. as one legal divorce)?" Ibn `Umar said, "Of course." Narrated Yunus bin Jubair: Ibn `Umar said, "The Prophet (ﷺ) said to `Umar, 'Order him (Ibn `Umar) to take her back.' " I asked, "Is such a divorce counted (as one legal divorce)?" Ibn `Umar said, "What do you think if someone becomes helpless and foolish?"