Sadly, it is true that most of the unspeakable horrors of this world in all ages have been committed by the religious.
“We can not choose the time in which we are born, but we can choose ourselves in this time. Exists only one race - a race of mankind, there is only one religion - religion of love, there is only one language - the language of the heart.” (C.S Lewis)
If only it were true and all other pompous, murderous zealotry were banished from the earth.
horrors of this world in all ages have been committed by the religious
religious what? Certainly not religious Christians.
In fact the worst of all have been the fanatic non religious ideologies including the spectrum of Communist systems. Perhaps as evil are the self described ROP-the cult founded by Mohamed.
Then you haven't read very much about history. There have been far more atrocities committed in the name of atheistic socialism than ANY religion ever dreamed of. One hundred million in the previous century alone.