Most religions don't condone genocide directly in their texts, but do mandate charity and generosity. It's tyranny using religion as a guise by dictators to seem justified in their goals (along with other subtle force tactics for those who aren't scare). The only leader that comes to mind that probably was actually killing because he thought a deity mandated is Philip II, but there will always be crazy people who occasionally rise to power, religious or not.
Whether or not leaders thought their deity was directly mandating them to commit violent acts doesn't alter the number of violent acts that were committed in the name of religion.
christianity teaches good morals
>Implying christianity is required for these morals
not...having love until marriage
This probably existed mostly to prevent conception of children until after couples were married, to ensure that both parents were there to provide for the child.
But with knowledge of proper contraception, it's not mattering anymore to an increasing amount of people.
Not to mention marriage isn't permanent anymore and can be easily broken off, leaving that concern meaningless