For more than 26 years, Pope John Paul II traveled the world with a silver pastoral staff topped with a dramatic, abstract crucifix crafted by the 20th-century artist Lello Scorzelli.

This symbol of papal ministry was first used by Pope Paul VI at the Second Vatican Council finale and has been carried on occasion by subsequent popes. But, year after year, Mass after Mass, it became a powerful symbol of the life of John Paul II -- now St. John Paul II -- during the second longest papacy in history.

John Paul II used this staff during his inauguration Mass and so did Pope Leo XIV, during the May 18 rite that fell on the 105th anniversary of John Paul II's birth. The new pope also wore an iconic chasuble -- the outer liturgical cloak -- that is now considered a relic of St. John Paul II.

With the fisherman's ring and the lambswool pallium over his shoulders, these links to John Paul II helped Leo XIV stress the need for unity and core Catholic traditions.

"The Apostle Peter himself tells us that Jesus is the stone that was rejected by you, the builders, and has become the cornerstone. Moreover, if the rock is Christ, Peter must shepherd the flock without ever yielding to the temptation to be an autocrat, lording it over those entrusted to him," Leo XIV told the flock of 150,000 assembled in St. Peter's Square.

"Brothers and sisters, I would like that our first great desire be for a united Church. … This is the missionary spirit that must animate us; not closing ourselves off in our small groups, nor feeling superior to the world."

But Leo XIV faces painful challenges, even while calling for unity.

Raymond Arroyo of the Eternal Word Television Network, and Fox News, tweeted on X: "Pope Leo at his Inaugural Mass, in a subtle reference to his predecessor, says 'Peter (the Pope) must shepherd the flock without ever yielding to the temptation to be an autocrat.' … He then pledged to be a source of unity."