"What's in a name?" the lover's question in Shakespeare's Romeo and Juliet is often quoted. In the Bible, there is indeed a lot in a name. Abram is given a new name, for God called him to assume a new role in the history of salvation. So, too, Jesus gave Cephas a new name, Peter, because of the role he was to play in the Church.
Similarly, a new Pope takes a new name. This custom began with Pope John II. His birth name was Mercurius, the name of a pagan "god" and the newly elected Pope felt he should have a proper Christian name.
God, the eternal lover, spoke through the prophet Isaiah: "I have called you by your name, and you are mine" (Isaiah 43:1). These words aptly describe the call of Abraham, the call of Mary, the call of Peter. If we are willing to accept them, these words also describe our own calling to be children of God and to assume our own role in the history of salvation.
In baptism we receive a new name, a saint's name. Our baptismal name reminds us that we belong to a community in which those in heaven serve as a model for us to imitate.
Father in Heaven, You have called me by my name and I am Yours.