Napoleon's Nightingale said:
Yes they did. Apparently you've never heard of the Dark Ages.
You must mean the Dark Ages when Christianity was the sole preserver of learning, education and the historical record. The Dark Ages followed the collapse of the Roman Empire and European decline into tribalism, not induced by Christianity or perpetuated by Christianity. Out of that grew corruption of the church, but historians that are honest recognize that the church stepped into an authority role at least in large part to prevent further chaos.
Like all things, a philosophy's value is determined by how it is applied. There are more passages in the bible encouraging violence, murder, and genocide than in any other religious text.
That would of course be for two reasons: 1) it's the largest if taken as a whole; 2) it demonstrates the progression of human understanding of the divine-human relationship which critics generally do ignore. The problem, my friend, is that you are comparing apples and oranges. In the former case to combine all sacred teachings of Hinduism, limiting it to the Gitas, you would find more violence advocated for. The Qu'ran is also, for its relative size, more violent than the Judeo-Christian canon.
In the Qu'ran you also do not have the divine-human relationship developed over centuries, you have one person's impression of God given in half of a lifetime. The unique nature of the Bible is that it provides a composite understanding of divine-human relationship over roughly 2000 years. No other religion has that rich of a composite canon. And through that we see human understanding molded and shaped until, by the time of the prophets and in the New Testament there is no understanding that violence, genocide and ethnic cleansing are okay.
Every religion has it's dark teachings. Again, it's a matter of how those teachings are put into practice.
If you cut and paste the teachings rather than reading the depth that is true.
Christianity has more blood on it's metaphorical hands than any other religion in history to date.
This is completely untrue. National Socialism, Aryan Supremacy and other campaigns of Ethnic superiority, Shintoism, Secularism and Nihilism, Jihadism, the "Civilizing/Pacifying" doctrines behind colonialism, Manifest Destiny, all are religions responsible for more mayhem and murder than Christianity. You are confusing political manipulation of the masses with religion. All religions encounter people who manipulate their adherents with false teaching with cut-and-paste religiosity, but the religion is not to blame.
For instance, humanity drapes every war in religious terms, it's called sacralization, or declaring something holy after the decision has been made to make it palatable. Saddam Hussein cloaked his gassing of the Kurds in religious terms, the Popes dressed the military conquest called the Crusades in religious terms (but read Jonathan Riley-Smith and other historians of the Crusades and they will explain that religiosity was exploited to get lesser sons of nobles out of Europe so they would quit the petty turf wars), the Japanese military embraced Shintoism as justification for tearing Nanking to pieces. To blame religion is to take too simplistic a way out and so miss the real culprits of history: the rise of the nation state, the creation of empires, systemic racism, colonialism and Cold War.
See the simplistic way to view the War on Terror is to label it a war on Islamo-facism, or whatever just to tie the war to Jungian style typology that releases two images in our collective memory. In this case a stereotype of Arab and stereotype of a Nazi. Both have religious implications and perhaps negative racial-religious connotations, though not necessarily so, unless the state defines them somehow as a threat. We may have a gut reaction prior to the state's involvement but it is the state's pronouncement that actualizes the response. And suddenly, to be Arab=Islamist=terrorist=facist=nazi=enemy. Never mind that Islam is a global religion with adherents, I think, in every tribe. But the real point is that religious identity is often manipulated by the state with the result that the impression is that the enemy isn't quite human. And if the state does not have a theological religion, it will create a secular religion: National Socialism and Communism are examples of this phenomenon.
This distracts us from the reality in much the way the French nationalism in the opening days of WW1 led to utter disaster, well presented and with more detail than I can remember in
Guns of August by I think Barbara Tuchman. The French officers told French troops that if they were brave enough, if they had enough "elan" bullets would pass right through them without harming them. Well the first half of the proposition came true for tens of thousands on the first few days, but obviously the second half did not and I forget how many divisions just ceased to be because nearly every soldier died. You can blame violence on religion, but you're looking in the wrong direction. It's not religion that produces the violence, it's nationalism/tribalism but that's an easy mistake to make because nationalism is often expressed in religious terms to "fire up the masses" and demonize the enemy. Just look at what happened in Rwanda in '94. Hyper-tribalism created by Belgian colonialism and Cold War neglect.
My point in all this is: by blaming religion, we ignore the other, and more directly causitive, agents. In doing so we prevent the formation of lasting peace. We do not see this present War on Terror as a consequence of the failings of colonial and Cold War strategies. We do not understand then that the violence is an expiation of our own manifest sins of violence and neglect when a butcher was ruler there. Instead we look for a religion to blame. It's easier, but it will never get us to the real culprit and so instability and suffering for all peoples will continue. The God of all religions longs for the day when children of the divine will, "beat swords (guns, tanks and bombs) into plowshares (tractors, combines and water wells)" and "when the Lion (of Islam) will lay down with the Lamb (of Christianity)" alongside "children of Abraham" and all others the world over.
So can you see why I can say Christianity was never communist, though was influencial in the development of communist ideology. The two systems are not constitute for the same purpose.