The Church is growing fastest in poorer, developing countries. This means that many of the Pope's followers have very little money and may not be getting their basic human rights.
Because of this some Catholics will want the Church to be about changing the world so that poor people get a better deal.
Other Catholics think their Church must be just about religion and should not get involved in politics.
In many richer Western countries fewer Catholics are bothering to go to Mass (church service).