See what you consider of evil is not completely true , but then again that on itself is not false either.You see the Catholic Church, of which you criticise, was rather evil to your perception or rather evil to you, as you see it. How ever the ones ruling the catholic system think what they're doing is right.
In an other instance, when a war is raised, one side thinks the other to be evil.
So I think the perception of good , or evil is just mere words and there are no true definition of good or evil.
It is how we perceive a situation or a person or anything that gives us the concept of it being good or evil.
It is because ,that there is no proper definition of good or evil that all kinds of chaos and wars are raised, for one something is good, for the other it is evil.

in the end "GOOD" or "EVIL" is nothing but just a standpoint , or how we perceive it.