First the person who threw the child over the railing is not a Muslim. In fact he has been treated for mental illness (although not obviously well enough.) There has been no discussion of what church he was raised in, if one at all. You probably got the idea from some fake news outlet.
It is my opinion that there are just as many similar quotations in the Christian bible. Remember the crusades. Christians tried to kill all Muslims around the world in the name of god!!!!! Thank goodness reasonable sane people today do not misinterpret the Koran and the Bible as it was written.
I seem to remember the Pope not being critical of Hitler killing all the Jews. Than goodness today the church has changed from that position.