When a new Pope is elected in the Catholic Church one of things that will change is their name.
For Example :Cardinal Joseph Ratzinger became Pope Benedict XVI. His predecessor, Pope John Paul II, was born Karol Jozef Wojtyla. And so on back through history.
Such practice made people to wonder why do Popes change name when they are elected
The first instance of a pope taking a different name upon his election as pope was John II in 533. John II’s given name was Mercurius, but he didn’t think that it would be appropriate for the pope to have a name taken from a pagan god (Mercury), so he took the name of a previous pope, John (thereafter known as John I), who had died as a martyr and was venerated as such.
But the roots may date back even further to the apostle Simon, a fisherman whom Jesus renamed Peter, appointing him to build his church after he was crucified. Roman Catholics consider Peter to be the first pope.
Popes take a new name to honor a past Saint who they take as role model or take a name of the previous Pope whom they admire , signifying that they will take up the work of the particular Pope , continuing from where the Pope stopped.
Pope John Paul II — Benedict XVI’s predecessor — chose his name to honour his predecessor, Pope John Paul I, who died just one month into his reign. By assuming his name, John Paul II signalled his intention to continue the previous pope’s work during his papacy.
Pope John Paul I had also paid tribute to previous popes. His moniker was a composite of the names of two previous popes, John and Paul, who had guided the church through the tumultuous Second Vatican Council (known as Vatican II) in the 1960s. Many consider it to be one of the most important and controversial periods in the church’s history, as leaders attempted to modernize relations between the church and the secular world.
In conclusion, when God choosed some his Prophet or disciples in the Bible their names are usually changed e.g Abram to Abraham, Saul to Paul .
The same applies to many religious association in the Catholic Church