CCC 874 Christ is himself the source of ministry in the Church. He instituted the Church. He gave her authority and mission, orientation and goal:
In order to shepherd the People of God and to increase its numbers without cease, Christ the Lord set up in his Church a variety of offices which aim at the good of the whole body. The holders of office, who are invested with a sacred power, are, in fact, dedicated to promoting the interests of their brethren, so that all who belong to the People of God. .. may attain to salvation.1

1 LG 18.