Pope Francis has warned the Catholic Church against deceiving itself that it is self-sufficient, instead emphasising its dependency on Christ.

"The church cannot deceive itself into thinking that it shines with its own light", the Pontiff said in his homily at a Mass today celebrating the feast of the Epiphany.

"Christ is the true light that brightens; and to the extent that the Church remains anchored to him, to the extent that it lets itself be illuminated by him, it is able to illuminate the lives of individuals and peoples."

In his message during the Mass in St Peter's Basilica for Epiphany, which commemorates the visit of the three Magi to Jesus, he called the Church to centralise mission, seeing it as vocation of the Church essential to its identity.

"Proclaiming the Gospel of Christ is not simply one option among many we can make, nor is it a profession," he added.

"For the Church, being missionary does not mean proselytizing. For the Church, being missionary means to express its very nature, being illuminated by God and reflecting his light."

"How many people wait for us [to have] this missionary commitment because they need Christ, because they need to know the face of the Father?" he asked.

The call to the "shining the light of Christ" and the vocation of mission was accompanied by a message of unity illuminated by the example of the magi. He said the narrative of the three gentile men visiting the Jewish Jesus reveals God's desire to unite all people.

"The magi... are living witness of the fact that the seeds of truth are present everywhere because they are gifts of the Creator who calls us to recognise him as good and faithful Father," he said.

"In front of Jesus, division of race, language and culture no longer exist. In that Child, all humanity finds its unity."

Pope Francis called the Church to be the equivalent to the magi's star for those who today "live with a 'restless heart' that continues to question without finding answers that are certain".

"They are looking for the star that leads the way toward Bethlehem. It is here, in the simplicity of Bethlehem, where you find the synthesis of the life of the church," he said. "For here is the wellspring of that light which draws to itself every individual and guides the journey of peoples along the path of peace."