As you might guess, being officially in a coalition with an avowedly Christian party meant that the SED did try to appeal to Christians. Ulbricht, for instance, declared that socialism and Christianity both had humanist foundations. Thomas Müntzer, the radical Protestant leader opposed by Luther and praised by Engels in his work
The Peasant War in Germany was a popular subject in East German historiography, and used to court Christians:
http://www.calvin.edu/academic/cas/gpa/muntzer.htmUlbricht even proclaimed a "Ten Commandments of Socialist Morality" in 1958:
Quote:1. Thou shalt always defend the international solidarity of the working class as well as the permanent bonds that unite all socialist countries.
2. Thou shalt love thy Fatherland and always be ready to defend worker and peasant power with all thy strength and capacity.
3. Thou shalt help to eliminate the exploitation of humans by one another.
4. Thou shalt perform good deeds for socialism, since socialism produces a better life for all working people.
5. Thou shalt act in the spirit of mutual support and comradely cooperation during the construction of socialism, respect the collective, and take its criticisms to heart.
6. Thou shalt protect and increase the property of the people.
7. Thou shalt always pursue ways to improve thy performance, be thrifty, and strengthen socialist work discipline.
8. Thou shalt rear thy children in the spirit of peace and socialism to become citizens who are well-educated, strong in character, and physically healthy.
9. Thou shalt live a clean and decent life and respect thy family.
10. Thou shalt exhibit solidarity with all those people who are fighting for national liberation and defending their independence.
One of the unique roles of the CDU was to represent the East German churches to the West Germans. The West German CDU, however, did not take its Eastern counterpart seriously and viewed it as an impotent mouthpiece of the SED.
In the late 80's the CDU did play a role in the dissident movement, using churches as centers for such activity.
As for the church itself, the vast majority of East Germans were Christians and both the Protestant and Roman Catholic churches existed and, until the late 80's, didn't cause much trouble for the government. One way such trouble was checked was the defeat of a late 40's proposal for the CDU and other parties to have their own youth organizations. The SED's view that the Free German Youth should be the only youth organization won out. Relations with the West German churches were also severed during the 50's (though contacts revived in the 70's onwards.)
And yes, after 1956 the Polish church regained some of its traditional privileges, even including religious education in schools. Yugoslavia's policy was also pretty lax, though not to the Polish extent. As for Romania, Hungary, Czechoslovakia and Bulgaria, their relations with the church were strained but there was still the whole freedom to worship thing, churches continued to operate, etc. It was only in Albania that churches and all clergy were forcibly suppressed and the act of worship practically made illegal.