The Protestant and Catholic Churches receive 602 million euros in state benefits from the federal states every year. Since the Second World War, this has amounted to around 20 billion euros. They are general state funds that have nothing to do with the church tax. They are paid by the federal states for the fact that church property has been “secularized”, i.e. expropriated, by the state in the past centuries.
In the case of the evangelical church, this happened after the Reformation. For the Catholic Church, the Reichsdeputationshauptschluss of 1803 is particularly authoritative.
However, when one draws upon history to make claims today, one should fully appreciate it.