That's easy. The Koran is full of evil and insanity.
"Then, when the sacred months have passed, slay the idolaters wherever ye find them, and take them (captive), and besiege them, and prepare for them each ambush. But if they repent and establish worship and pay the poor-due, then leave their way free. Lo! Allah is Forgiving, Merciful."
"The only reward of those who make war upon Allah and His messenger and strive after corruption in the land will be that they will be killed or crucified, or have their hands and feet on alternate sides cut off, or will be expelled out of the land. Such will be their degradation in the world, and in the Hereafter theirs will be an awful doom;"
Men are the maintainers of women because Allah has made some of them to excel others and because they spend out of their property; the good women are therefore obedient, guarding the unseen as Allah has guarded; and (as to) those on whose part you fear desertion, admonish them, and leave them alone in the sleeping-places and beat them; then if they obey you, do not seek a way against them; surely Allah is High, Great."
"Remember thy Lord inspired the angels (with the message): "I am with you: give firmness to the Believers: I will instill terror into the hearts of the Unbelievers: smite ye above their necks and smite all their finger-tips off them."