Yahya related to me from Malik from Hisham ibn Urwa that hisfather said, "It used to be that a man would divorce his wife and thenreturn to her before her idda was over, and that was alright, even ifhe divorced her a thousand times. The man went to his wife and thendivorced her and when the end of her idda was in sight, he took herback and then divorced her and said, 'No! By Allah, I will not go toyou and you will never be able to marry again.' Allah, the Blessed,the Exalted, sent down, 'Divorce is twice, then honourable retentionor setting free kindly.' People then turned towards divorce in a newlight from that day whether or not they were divorced or notdivorced."
USC-MSA web (English) reference: Book 29, Hadith 80
Arabic reference: Book 29, Hadith 1242