ما هو الدليل من القرآن أو السنة على جواز زواج الأخ من أخته في شرع آدم عليه السلام؟

Allah created Adam and Eve as the origin of humanity, and mankind procreated from them. Scholars have mentioned that Allah permitted Adam to marry his daughters to his sons due to necessity. Thus, he would marry the male of one womb to the female of another. As an example, Ibn Kathir mentioned that Qabil and Habil offered sacrifices to determine who would marry Qabil's beautiful sister. The sacrifice of Habil was accepted, while that of Qabil was not, which led to Habil's murder. This marriage was necessary for the continuation of human lineage.