Great harm has been done by those calling themselves Christian. Critics (especially atheists) are eager to point this out.(1)
However, criticisms of Christianity are often half-truths.
The Crusades for example.
How many times have you heard the Crusades brought up without mentioning they were a response to violent Muslim aggression? Muslims had previously captured the Holy Land, destroyed churches and killed Christians who refused to convert to Islam.
Aspects of the Crusades were terribly wrong,(2) but they should be put in historical context.
And why not mention the evil done by atheism? Atheistic Communism terrorized and oppressed half of Europe for 40 years. Stalin alone killed 20-60 million.(3)
Lastly, we need to look at the whole picture. Christianity has built more schools and hospitals, helped more needy and outcast, and brought hope to more people than atheism ever will. The good far outweighs the bad.
Let's recognize sin committed in the name of Christ, but let's be honest about it.
(1) I believe most of the evil done in the name of Christ is done by Christians in name only, not genuine believers. To judge Christianity by the bad cases is not intellectually honest.
(2) The slaughter of Jews during the Crusades was especially evil, but fades in comparison to Nazi Germany.
(3) I realize this is a broad estimate, but so much of Stalin's evil practices were kept secret that it's hard to be accurate.
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