A man married a woman from Banu Shumakh, then he saw her mother and liked her. He asked Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him): "I have married a woman but have not yet had relations with her, then I liked her mother. Can I divorce her and marry her mother?" He replied: "Yes." So he divorced her and married her mother. Later, Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) went to Madinah and asked the Companions, and they said: "This marriage is not permissible." Then he returned and went to Banu Shumakh and asked: "Where is the man who married the mother of the woman who was previously in his marriage?" They told him that he was there. So he said: "He must separate from her immediately." The people said: "But she has become pregnant!" Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: "Even so, he must separate from her immediately, because she is forbidden to him by Allah, the Mighty and Majestic."
Hadith Referenceسنن سعید بن منصور / كتاب التفسير / 601
Hadith Gradingمحدثین:سنده فيه حديج بن معاوية وتقدم أنه صدوق يخطئ، لكنه لم ينفرد به، وفيهبو إسحاق السبيعي وهو مدلس
Hadith Takhrij«أخرجه سعيد بن منصور فى (سننه) برقم: 601، 936، والبيهقي فى(سننه الكبير) برقم: 10612، 14016»