Ibn Abbas narrated that: “At the time of the Messenger of Allah صلى الله عليه وسلم and Abu Bakr, and for the first two years of Umar’s caliphate, the pronouncement of three divorces in one was regarded as one. Then Umar ibn al-Khattab said, “The people are being hasty with regard to something in which they should take their time. It would be better for us to let it stand (i.e. to let it count as three divorces),” so he let it stand.”

Sahih Muslim, Kitab al-Talaq, #1472