Within the Catholic Church, there have been the following disputes for centuries: Must wine be provided for all the faithful participating in the Mass or only for the priest? Must it necessarily be white wine or red wine, or is that irrelevant? May the wine be mixed with water? Are grape juice, sparkling wine or other drinks permitted instead of wine? And how does one deal with these questions, which are hotly debated by many highly educated clergy, or with the problematic consumption of alcohol by children, the sick and alcoholics? And last but not least: Does wine (Mass wine) have to be produced in a special way according to certain "Christian" rules?