On the morning after his election as the 267th Pope, Pope Leo XIV celebrated Mass with the Cardinal electors in the Sistine Chapel, where he offered a heartfelt homily calling the Church to bear joyful witness to faith in Christ, while cautioning that life loses meaning where faith is lacking.

The newly elected Pope, born in the United States, began his address by thanking the Cardinal electors for their trust, quoting the Responsorial Psalm: "I will sing a new song to the Lord, because He has done marvels." He urged the Cardinals to reflect on the blessings poured out on the Church through the ministry of Peter and expressed hope in walking with them as a united Church to proclaim the Gospel.

In his homily delivered in Italian, Pope Leo reflected on the confession of St. Peter in the Gospel of Matthew: “You are the Christ, the Son of the living God.” He emphasized that this enduring profession of faith, handed down through apostolic succession, remains the foundation of the Church's mission. He described Jesus as the one who reveals the face of God and offers a model of human holiness and a promise of eternal destiny that transcends human limitations.

Pope Leo noted that the recognition of Jesus as the Christ is both a divine gift and a path that transforms those who receive it. He reminded the faithful that they were chosen by God before birth and entrusted with the mission of proclaiming the Gospel to all people.

Reflecting on his own election the previous day, Pope Leo said he had been entrusted with a sacred treasure to be a faithful steward for the entire Church. He pointed to Jesus’ question to the disciples, “Who do people say that the Son of Man is?”, as central to the Church’s mission in today’s world.

The Pope warned of two prevalent attitudes in response to this question—one that rejects Christ when His teachings become uncomfortable, and another that respects Him merely as a good man but not as the Son of God. These, he said, mirror contemporary views in a world where faith is often seen as absurd and irrelevant.

He highlighted the increasing difficulty in bearing witness in societies where technology, power, and pleasure are placed above spiritual truth, and where believers are often mocked or dismissed. Yet, he stressed, these very places are where the Church’s missionary outreach is most needed.

Pope Leo lamented that a lack of faith often accompanies a loss of meaning in life, a weakening of family bonds, and widespread moral confusion. He also warned against the rise of "practical atheism" among the baptized, where Christ is reduced to a mere inspirational figure.

Despite the challenges, Pope Leo reassured the faithful that this is the world entrusted to the Church. He called on Christians to reaffirm their faith with Peter’s words: “You are the Christ, the Son of the living God.”

He urged all believers to deepen their personal relationship with Christ through a daily journey of conversion and to witness their faith together as a Church. As he begins his ministry as Bishop of Rome, the Pope said he embraces the mission to preside in charity over the universal Church.

Recalling the example of Saint Ignatius of Antioch, who was martyred in Rome, Pope Leo emphasized the need for those in authority to humble themselves so that Christ may be glorified. He concluded his homily with a prayer, entrusting his papal ministry to the intercession of Mary, Mother of the Church.