The third major foundation of Marxism is the idea that only once the proletariat has overthrown the bourgeoisie and gained control of the means of production can true equality exist. Marx believed that this overthrow must be violent in nature. He believed that the revolution must happen quickly and succinctly and therefore must be violent. Only by using violence would the proletariat succeed in gaining control of the means of production.
It is at this point where Christianity and Marxism cannot be reconciled. The message of Jesus Christ was a message of peace. There is never a point where I could imagine Christ espousing violence in any matter for any matter. From the Ten Commandment injuction "Thou Shall Not Kill" to Christ's Sermon on the Mount never could violence ever be a part of a Christian's life. I believe this to be true whether your attempting revolution or defending democracy. Violence is unacceptable according to the teachings of Christ and he lived out his words by being crucified rather than use the powers at his disposal to fight an unjust government.
The early Christians followed Christ's lead. Nowhere in the New Testament do you find Christians using violence to defend themselves. Instead they choose to be martyred. Violence implies that either rage or greed rests in your heart. Many use violence to protect their interests or their rights and Christ preached against being obsessed with both. Christians aim for a peaceful revolution led by love and Spirit-led conduct. I wrote more on this subject in my Christian Manifesto published on this blog some months ago.
So it is at this point where the greatest divergence occurs between Christianity and Marxism. Do I believe someone can be a Christian Marxist? Yes, but only if they denounce violence as the means to justice. As Camus said..."an end that requires unjust means is an unjust end."