"Since all the faithful form one body, the good of each is communicated to the others.... We must therefore believe that there exists a communion of goods in the Church. But the most important member is Christ, since he is the head.... Therefore, the riches of Christ are communicated to all the members, through the sacraments." "As this Church is governed by one and the same Spirit, all the goods she has received necessarily become a common fund."
Source: Catechism of the Catholic Church (Vatican.va)