There is one Catholic Church led by the pope, while there are many Protestant communities. We all share our faith in God and in God’s love for mankind. But there are also differences. As Catholics, we believe that God’s revelation is disclosed in the Bible and in the Tradition of the Church, whereas most Protestants only recognise the Bible as a source of revelation.
Most Protestants also have problems with the sacraments, the role of Mary and the saints, and the position of the pope. Jesus wanted to institute a single Church: the divisions that exist between Christians are not in accordance with his intention. This is why we need to pray a lot and do everything we can to work for unity (ecumenism).