Hazrat Sa'id bin al-Musayyib (may Allah have mercy on him) said: "If a man makes an oath of abstinence (ila') from his wife and four months pass, the ila' does not take effect until he gives divorce." I said: "Hasan (may Allah have mercy on him) says that after four months, one irrevocable divorce (bainah) takes place." He said: "When you meet Hasan, convey my greetings and tell him that he has said something very wrong."
Hadith Referenceسنن سعید بن منصور / كتاب الطلاق / 3059
Hadith Takhrij«أخرجه مالك فى «الموطأ» برقم: 2047، وسعيد بن منصور فى «سننه» ترقيم الدرالسلفية برقم:، 1882، والبيهقي فى«سننه الكبير» برقم: 15324، وعبد الرزاق فى «مصنفه» برقم: 11652، وابن أبى شيبة فى «مصنفه» برقم: 18874، 19628»