Communism advocates the establishment of a "classless society". In actuality it is dominated by a self appointed Nomenklatura. It officially prohibits one person from employing another, which leads to massive restrictions on personal freedom and economic shortages of every sort of goods and services. It does not allow for savings and investment, the ownership of private property, such as homes or cars, or even fair payment of wages and labor. Persons born in Communist countries have no citizenships rights.
Communism and Atheism
Marx coined the saying "Religion is the opium of the people" expressing his view that religion, and in particular state-endorsed religion, has been used for centuries as a form of social control by promising the downtrodden a better life in a mythical hereafter to deter them from trying to build one here and now by removing the chains of their masters and overthrowing the capitalist system that oppressed them. Karl Marx wrote: "Communism begins from the outset (Owen) with atheism; but atheism is at first far from being communism; indeed, that atheism is still mostly an abstraction." 
Vladimir Lenin similarly wrote: "A Marxist must be a materialist, i. e., an enemy of religion, but a dialectical materialist, i. e., one who treats the struggle against religion not in an abstract way, not on the basis of remote, purely theoretical, never varying preaching, but in a concrete way, on the basis of the class struggle which is going on in practice and is educating the masses more and better than anything else could."
Theory and horror
It is based upon a socialist economy in which the public, whether the state or other group, owns the "means of production" and in which the wealth of the nation is rationed among the Party's beneficiaries. Yet party members (there is only one Party) have special stores in which ordinary people are barred, stores which are immune to the perennial shortages which the lower class must endure (see queuing).
Various Communist doctrines have evolved or been adapted to the time and place they have been implimented. Marxism, developed by Karl Marx, and its modifications under Vladimir Lenin, Joseph Stalin, and Mao Zedong, advocates the overthrow of the exisitng order by a revolution of the proletariat, the social group which does not control the means of production. The goal of Marxism is supposedly to create a classless society which would result in nolonger the need for any government.
The most famous government to label itself "communist" is the former USSR or the Union of Soviet Socialist Republics; the Communist Party controlled its government from 1922 to 1991. This government was officially atheist and attempted to suppress all religion. Like many authoritarian regimes, it tried to cultivate reverence for the state as a psychological substitute for religion. Left-wing critics of the USSR charged that it was communist in name only, and had betrayed the revolution which founded it. George Orwell expressed this viewpoint eloquently in his 1945 fable Animal Farm.
Marxist theory is intended to appeal to its adherents with the phrase, "from each according to his abilities, to each according to his needs", which essentially states point blank a worker does not get paid according to his abilities, and there is no incentive within the economic theory. Another quote by Marx was, "The theory of the Communism may be summed up in the single sentence: Abolition of private property," i.e. legalized theft.
Marx also coined the disparaging atheistic dictum "religion is the opium of the masses", expressing the fundemental Marxist view that the proletariat have been brainwashed by religion, and thus a Nomenklatura of enlightened party members with this esoteric knowledge and foresight are justified in enslaving the masses, for their own benefit.
Communism and Atrocities and Repression
Modern communist regimes have engaged in mass killings on a scale of millions of individuals.  A work entitled The Black Book of Communism published by the Harvard Press focuses on the crimes, terror, and repression of modern communist regimes over a 70 year period.  This book is fairly controversial partly due to the various estimates regarding the millions of people who died under communist regimes. 
Similarly, a influential book which concerns itself with Russian communist torture, repression and attrocities is Aleksandr Solzhenitsyn's The Gulag Archipelago which won Solzhenitsyn a Noble Prize.  In 1983, Alexander Solzhenitsyn in which he gave his explanation of the cause of why millions of people died under Russian communism:
"Over a half century ago, while I was still a child, I recall hearing a number of old people offer the following explanation for the great disasters that had befallen Russia: "Men have forgotten God; that's why all this has happened.
Since then I have spend well-nigh 50 years working on the history of our revolution; in the process I have read hundreds of books, collected hundreds of personal testimonies, and have already contributed eight volumes of my own toward the effort of clearing away the rubble left by that upheaval. But if I were asked today to formulate as concisely as possible the main cause of the ruinous revolution that swallowed up some 60 million of our people, I could not put it more accurately than to repeat: "Men have forgotten God; that's why all this has happened." 
In communist North Korea, abuse and killing in prison camps is occurring today.  In addition, the North Korean government practices brutal repression and atrocities against North Korean Christians. 
In 1999, the publication Christian Century reported that "China has persecuted religious believers by means of "harassment, prolonged detention, and incarceration in prison or `reform-through-labor' camps and police closure of places of worship."  In 2003, owners of Bibles in China were sent to prison camps and 125 Chinese churches were closed.  China continues to practice religious oppression today. 
Between 1989 and 1991, many communist governments were overthrown. The Berlin Wall in Germany, which had become a symbol for the division between the West and communist states, was torn down largely in response to Ronald Reagan in 1989, and there was also a large revolution against Romanian dictator Nicolaie Ceausescu. In 1991, the USSR broke up into several countries. Some of these remained under autocratic governments, but some have embraced democracy.
Although Communism's influence has decreased dramatically in Europe, around a quarter of the world's population still lives under Communist Party rule.
The most famous of those countries governed by a communist one-party system is China, but others (such as North Korea, Laos, and Vietnam) remain. There is considerable debate as to the extent to which these governments actually implement communist policies. China has not democratized (note especially the crushing of the Tiananmen Square protests of 1989), but its economic policies have been called "red capitalism" by some commentators, as there is a growing sector that behaves in a less-regulated, free market style. China's economy manufactures a wide variety of products that are sold to non-communist countries, and there is quite obvious tolerance of economic inequality, with some provinces struggling with poverty while others prosper.
One of the only remaining Modern communist countries, Cuba, is still kept under economic repression by the USA due to its communist beliefs. Over 100 UN countries are still calling for an end to this highly illegal blockade of trade and services.
Communists cite scripture
Some Communist ideaology has made its way into the Church as a Social Gospel, interpreting the Gospel as less redemptive of sin and more of a public works campaign and activism. The often cite Jesus feeding the masses and warnings to the wealthy who believed self-seeking is all this world has to offer. Communists often cite the Acts of the Apostles, as early Christians practicing some form of sharing for the common good:
- And all that believed were together, and had all things common; And sold their possessions and goods, and parted them to all men, as every man had need. (Acts 2:44-45, KJV)
- Neither was there any among them that lacked: for as many as were possessors of lands or houses sold them, and brought the prices of the things that were sold,
- And laid them down at the apostles' feet: and distribution was made unto every man according as he had need.
- And Joses, who by the apostles was surnamed Barnabas, (which is, being interpreted, The son of consolation,) a Levite, and of the country of Cyprus,
- Having land, sold it, and brought the money, and laid it at the apostles' feet.(Acts 4:34-7, KJV)
But as Arnold Toynbee has pointed out, this Marixt view denies the most crucial points,
- The passage in the Acts represents the philanthropy of the primitive Christian Society as flowing from a God-given grace which was the fruit of a belief in the divinity of Jesus. In other words, the charity which is here depicted as moving the primitive Christians to go—in their mutual concern for one another's welfare—to the extreme length of sharing all their worldly goods is not a mere love of Man for Man (which is the limited literal meaning of the word ‘philanthropy’), but is a spiritual relation to which God is a party as well as His human creatures. In fact, this Christian Socialism is a practical application, on the economic surface of life, of the fundamental religious truth that the brotherhood of Man is a consequence of the fatherhood of God - a truth which is driven home with special force by a religion which teaches that God is not only the father and creator of Man, but also his savior who has been incarnate in human shape and has suffered, and triumphed over, Death.
Notes and references
- Victims of Communism Memorial Foundation, Documenting Communism's Crimes Against Humanity.
- Arnold Toynbee, A Study of History, Annex II to Vol. V, Part C (i) (c) 2, p. 585, Marxism, Socialism, and Christianity.