Meditate on Abraham and the sacrifice of his “son.”
Who is Ishmael? Who was the mother of that child? Who is Isaac? Who was the mother of that child?
Who gave her servant to Abraham for him to have a child since she was sterile?
Who asked that servant and her child to be banned when she finally got Isaac, by what is called a divine miracle?
Abraham is common to the three Semitic religion (and Christianity is originally a Semitic religion) with a slight change in the identity of the mother and son for the sacrifice in Judaism + Christianity as opposed to Islam.
The sacrifice of Ishmael and/or Isaac is teh founding stone of teh Islamic rift from Judaism and Christianity.