If Islam Does Not Allow You To Marry Your Siblings, Then Why Did Hazrat Adam's Children Marry Each Other?
As if Eve gave birth of one son and one daughter in one turn. Then these both brother & sister would not marry with each other. But they would marry with their other siblings who were born in the next turn. And that was the rule for some specific period of time. And it has nothing to do with religion Islam. Because there were several things which were allowed in previous religion but later on they were not allowed in the next era of religion. Because the wisdom of humanity also developed with the passage of time. For example the prostration of respect was allowed earlier. But later on Islam didn't allow it. Similarly first there were no medical threats in the beginning. But afterwards it may cause some harm. That's why Almighty God who is Exalted in Might & Wisdom didn't allow it later on. For the benefit of humanity.
But after some time when so many couples were married and they reproduced there children this law was terminated. Now you can say this was the demand of that time. Otherwise there was no other option available to reproduce or re-product and grow. I hope I answer your question and satisfy your self that why at that time it was allowed to marry between sisters and brothers and why is it prohibited in our time. There is another angle of this question which you can ask to a doctor, why it is prohibited to not marry with your sisters and advised to marry out of your family.
Adam sons didnt marry to there own sister at all. And if thats the case than mention the sister name .Quran mention Habil and kabil.
One brother kill another one out of jealousy.but what about the sister..
I liked your answer. It may rise in many minds. In early age there was no popullation except two persons Hazrat Adam and Hazrat Eve(Ama Hawa). There was a law that the cheldren born at morning will marry the children born at evening. It was the demand of time but later on when there were many people then this law was terminated.