No one gave him Prozac. He got a job herding sheep. And a wife. And two sons. And settled in a nice little community in a nice little church that his father-in-law pastored. Like most of us, content in our misery. The call to go evangelize half way across the African continent to a country where he was wanted for murder was not, shall we say, convenient.
Abram (“father”) was the one who got the vision and because he believed enough to obey he became Abraham (“Father of nations”) and received the covenant by which we today come to Christ, but the knowledge of the One God stretches back through Noah to Adam. If you want to know who Adam is, read Genesis 5:2. No really, if you’re now thinking “Adam was the first man”, you should just take 5 seconds to read it.
Those Muslims who seek and meet the One God of Abraham will understand he is not Allah (el-Ah, the violent moon god of Ur from whom Abraham departed) but that the One God of Abraham made a human body and lived inside it to save, not destroy, everything he has created.