What position did the Chinese Communists take regarding religion when they came to power

It can be said that Chinese Communists are atheist. however, they are more tolerant of other religions that they used to be. There is a diversity of religion in China today like Christianity and traditional Chinese religion groups. The constitution allows "freedom of religious belief". there are 5 official religions in China: Buddhism, Catholicism, Daoism, Islam, and Protestantism.

The communists do not allow religion within the Party, members might be banned from it if they reveal any religious sign.