Pope Francis starts his tenure humbly VATICAN CITY - In a busy first full day as head of the Roman Catholic Church, Pope Francis on Thursday showed that he intends to shun the trappings of high office and introduce a humble note to the papacy. The 76-year-old pontiff returned to the clerical residence in Rome where he had stayed before the papal conclave to pick up his luggage and settle his bill. "He paid the bill to set a good example," Vatican spokesman Father Federico Lombardi said. Driven around Rome in a Vatican car without an escort, Francis also showed up at the Basilica of Santa Maria Maggiore with little notice to offer a bouquet of flowers and pray. The pope, a Jesuit, visited the altar where the founder of the order, Ignatius of Loyola, held his first Mass after becoming a priest. "It seemed as if he had always been pope," said a priest at the church, Elio Monteleone. He was neither embarrassed nor intimidated, but very serene. The pope left after 30 minutes, stopping to wave to schoolchildren. By choosing to name himself after St. Francis of Assisi, who dedicated his life to helping the poor, Pope Francis appears keen to live up to the saint's reputation for humble simplicity. Francis was also the name of a prominent 16th century Jesuit who preached the Gospel in Asia. Lombardi said that after Cardinal Jorge Mario Bergoglio of Argentina was elected pope Wednesday, the pontiff remained standing as the cardinals pledged obedience to him, declining to sit on a throne as new popes are expected to do. After addressing the public, he opted not to return to the cardinals' Vatican residence in a papal car, but to ride on a minibus with the other cardinals. The son of Italian immigrants, the pope is in touch with cousins in Italy. One of them, Giuseppina Ravedone, told the Italian daily La Stampa that Bergoglio had refused to pay for expensive new vestments when he was made a cardinal in 2001, preferring to buy cloth and ask his sister to make them. The new pope's informal greeting to the crowds in St. Peter's Square bore "visible witness to his simplicity," said the Jesuit's superior general, Father Adolfo Nicolas. On Thursday afternoon, Francis sounded a stern note when he held his first Mass as head of the Roman Catholic Church in the Sistine Chapel before the cardinals who had elected him as the 266th pope a day earlier. Emphasizing the power of prayer, Francis said, "He who does not pray to the Lord prays to the devil. When we don't proclaim Jesus Christ, we proclaim the worldliness of the devil, the worldliness of the demon. Standing before Michelangelo's fresco of the "Last Judgment," the pontiff said, "When we walk without the cross, when we build without the cross and when we proclaim Christ without the cross, we are not disciples of the Lord. We are worldly. We may be bishops, priests, cardinals, popes, all of this, but we are not disciples of the Lord. Francis issued a strong warning to the cardinals, telling them the Roman Catholic Church risks becoming a compassionate nongovernmental organization unless it sticks to its spiritual path. Building a solid church, he said, was vital to stop it from crumbling like a sand castle built by children. Francis was elected as the Vatican faces a string of scandals concerning allegations of corruption and infighting and sexual abuse, which weakened the papacy of Benedict XVI, who resigned Feb. 28. The pope is expected to meet the College of Cardinals informally Friday and hold an audience with journalists Saturday. On Sunday, he is to give his first Angelus in St. Peter's Square. His installation ceremony is set for Tuesday.