‘ONE IN CHRIST, UNITED IN MISSION’

A message from Pope Leo XIV for the 100th anniversary of World Mission Sunday

In his World Mission Sunday message, Pope Leo XIV says “Let us all commit to contributing to the great mission of evangelization — which is always a work of love —according to our own vocation and the gifts we have received.” In the photo: Pope Leo is shown amid the faithful, on the day he led those gathered at the “Mama Muxima” Shrine in praying the rosary in Muxima, Angola, on April 19 during his apostolic journey to the country. Thirty-eight percent of Angolan children under 5 years of age are undernourished. (OSV News photo) (Courtesy photo of Guglielmo Mangiapane)

Dear brothers and sisters,

For World Mission Day 2026, which marks the centenary of a celebration established by Pius XI that is very dear to the Church, I have chosen the theme “One in Christ, united in mission.” Following the Jubilee Year, I wish to encourage the whole Church to continue its missionary journey with joy and zeal in the Holy Spirit. This requires hearts united in Christ, reconciled communities and, in everyone, a willingness to cooperate with generosity and trust.

As we reflect on being one in Christ and united in mission, let us allow ourselves to be guided and inspired by divine grace, “to renew in ourselves the fire of our missionary vocation” and advance together in the commitment to evangelization, in this “new missionary age” in the history of the Church (Homily, Jubilee of the Missionary World and of Migrants, 5 October 2025).

1. One in Christ — Missionary disciples united in him and with our brothers and sisters

The mystery of union with Christ lies at the heart of mission. Before his Passion, Jesus prayed to the Father, “that they may all be one. As you, Father, are in me and I am in you, may they also be in us” (Jn 17:21). These words reveal Jesus’ deepest desire, as well as the identity of the Church as a community of his disciples. That is, a communion that flows from the Trinity, and continues to be sustained by the Trinity. A communion at the service of fraternity among all human beings and harmony with all creation.

Being a Christian is not primarily about practices or ideas; it is a life in union with Christ, in which we share in his filial relationship with the Father in the Holy Spirit. It means abiding in Christ, like branches on the vine (cf. Jn 15:4), immersed in the life of the Trinity. This union gives rise to mutual communion among believers and is the source of all missionary fruitfulness. Indeed, just as Saint John Paul II taught, “communion represents both the source and the fruit of mission” (Apostolic Exhortation Christifideles Laici, 32).

In this context, the Church’s primary missionary responsibility is to renew and sustain spiritual and fraternal unity among its members. In many situations, we encounter conflicts, polarization, misunderstandings and a lack of mutual trust. When this occurs even within our communities, it undermines our witness. The evangelizing mission that Christ entrusted to his disciples requires, above all, hearts that are reconciled and eager for communion. Consequently, it is important to intensify ecumenical efforts with all Christian Churches, building upon the opportunities arising from the joint celebration of the 1700th anniversary of the Council of Nicaea.

Last but not least, being “one in Christ” calls us to keep our gaze fixed on the Lord, so that he may truly be at the center of our lives and communities, the center of every word, action and interpersonal relationship, leading us to say with amazement: “It is no longer I who live, but it is Christ who lives in me” (Gal 2:20). By constantly listening to his word and through the grace of the sacraments, it will be possible for us to become living stones in the Church. Today, the Church is called to take up the fundamental themes of the Second Vatican Council and the subsequent Papal Magisterium, in particular that of Pope Francis. In fact, as Saint Paul says, “we do not proclaim ourselves; we proclaim Jesus Christ as Lord” (2 Cor 4:5). For this reason, I reiterate the words of Saint Paul VI: “There is no true evangelization if the name, the teaching, the life, the promises, the kingdom and the mystery of Jesus of Nazareth, the Son of God are not proclaimed” (Apostolic Exhortation Evangelii Nuntiandi, 22). This process of genuine evangelization begins in the heart of every Christian in order to reach all of humanity.

Therefore, the more united we are in Christ, the better able we will be to carry out together the mission that he entrusts to us.

2. United in mission — That the world may believe in Christ the Lord

The unity of disciples is not an end in itself; it is directed toward mission. Jesus states this clearly: “So that the world may believe that you have sent me” (Jn 17:21). It is through the witness of a reconciled, fraternal and united community that the proclamation of the Gospel acquires its full communicative power.

From this perspective, it is worth recalling the motto of Blessed Paolo Manna, “The entire Church for the conversion of the whole world,” which succinctly expresses the ideal that inspired the establishment of the Pontifical Missionary Union in 1916. On its 110th anniversary, I convey my gratitude and my blessing for its commitment to inspiring and forming the missionary spirit of priests, consecrated persons and lay faithful, promoting the unity of all evangelizing efforts. In fact, no baptized person is exempt from or indifferent to mission: everyone, each according to their own vocation and condition of life, participates in the great work that Christ has entrusted to his Church. As Pope Francis repeatedly reminded us, proclaiming the Gospel is an action that is always harmonious, communal and synodal.

For this reason, unity in mission means safeguarding and nurturing the spirituality of communion and missionary cooperation. By daily fostering this attitude, divine grace gradually teaches us to see our brothers and sisters through the eyes of faith. We also learn to recognize joyfully the good that the Spirit inspires in each person, to embrace diversity as a treasure, to bear one another’s burdens and always to seek the unity that comes from above. Indeed, we all share in one mission in “one Lord, one faith, one baptism, one God and Father of all, who is above all and through all and in all” (Eph 4:5-6). This spirituality constitutes the daily expression of missionary discipleship. It helps us to recover a universal vision of the Church’s evangelizing mission, and to overcome a lack of coordinated efforts and the creation of factions among the followers of the one Lord — such as “I belong to Paul,” “I to Apollos” (cf. 1 Cor 1:10-12).

Needless to say, missionary unity should not be understood as uniformity, but rather as the convergence of different charisms for the same purpose, namely to make Christ’s love visible and to invite everyone to encounter him. Evangelization is achieved when local communities cooperate with one another and when cultural, spiritual and liturgical differences are fully and harmoniously expressed in the same faith. I therefore encourage all institutions in the Church to strengthen their sense of ecclesial missionary communion and to develop creative and concrete ways of cooperating with one another for and in the mission.

In this regard, I would like to thank the Pontifical Mission Societies for their service to missionary cooperation, which I experienced with gratitude during my ministry in Peru. These societies — Propagation of the Faith, Holy Childhood, Saint Peter the Apostle, Saint Peter the Apostle and Pontifical Missionary Union — continue to nurture and form missionary awareness for the faithful of all ages, and to promote a network of prayer and charity that connects communities throughout the world. Here, it is worth noting that the founder of the Society of the Propagation of the Faith, Blessed Pauline Marie Jaricot, established the Living Rosary 200 years ago. Even today it continues to bring together many of the faithful throughout the world to pray for every spiritual and missionary need. It is also worth remembering that, following a proposal from the Society of the Propagation of the Faith, Pius XI established World Mission Day in 1926. The annual offerings collected on this day are distributed by the society, on behalf of the pope, to support the various needs of the Church’s mission. The four societies, therefore, as a whole and each in its own specificity, still play a valuable role for the entire Church. They are a living sign of unity and ecclesial missionary communion. I invite everyone to work with them in a spirit of gratitude.

3. Mission to love — Proclaiming, living and sharing God’s faithful love

If unity is the condition of mission, love is its essence. The Good News that we are sent to proclaim to the world is not an abstract ideal; it is the Gospel of God’s faithful love, which became flesh in the face and life of Jesus Christ.

The mission of the disciples and the Church as a whole is to continue the mission of Christ in the Holy Spirit: a mission born of love, lived in love, and leading to love. In fact, the Lord himself, in his great prayer to the Father before his Passion, after invoking unity among his disciples, concludes: “so that the love with which you have loved me may be in them, and I in them” (Jn 17:26). Impelled by the love of Christ, the Apostles then went out to evangelize for Christ (cf. 2 Cor 5:14). In the same way, throughout the centuries, multitudes of Christians — martyrs, confessors and missionaries — have given their lives to make this divine love known to the world. Thus, guided by the Holy Spirit, the Spirit of love, the Church’s evangelizing mission will continue until the end of time.

I would like to express my special gratitude to today’s “ad gentes” missionaries. Like Saint Francis Xavier, they have left their homeland, their families and all sense of security in order to proclaim the Gospel and bring Christ and his love to places that are often challenging, poor, conflict-ridden or culturally distant. Despite adversity and human limitations, they continue to give themselves joyfully, because they know that Christ himself, and his Gospel, are the greatest treasures we can offer. Through their perseverance, they demonstrate that God’s love transcends all barriers. The world still needs these courageous witnesses of Christ, and ecclesial communities still need new missionary vocations. We must always keep them close to our hearts and continually pray to the Father for them. May he grant us the gift of young people and adults who are willing to leave everything behind to follow Christ on the path of evangelization even to the ends of the Earth!

Filled with admiration for men and women missionaries, I make a special appeal to the whole Church to join them in the mission of evangelization through the witness of our lives in Christ, through prayer and through our contributions to the missions. As Saint Francis of Assisi said, “Love is not loved,” and we look to him in a special way on the 800th anniversary of his passing to heaven. Let us find inspiration in his desire to live in the love of the Lord and to transmit it to those both near and far, because, as he said, “this love Who hath loved us much is much to be loved” (Saint Bonaventure of Bagnoregio, The Life of Saint Francis, chap. IX, 1; Fonti Francescane, 1161). Let us also draw inspiration from the zeal of Saint Thérèse of the Child Jesus, who declared that she would continue her mission even after death: “I shall desire in heaven the same thing as I do now on earth: to love Jesus and to make him loved” (Letter 220 to l’Abbé Bellière, 24 February 1897).

Inspired by these testimonies, let us all commit to contributing to the great mission of evangelization — which is always a work of love —according to our own vocation and the gifts we have received. Your prayers and practical support, particularly on World Mission Day, will be a great help in bringing the Gospel of God’s love to everyone, especially the poorest and those most in need. Every gift, no matter how small, becomes a meaningful act of missionary communion. I renew my heartfelt gratitude “for everything you will do to help me help missionaries throughout the world” (Video Message for World Mission Day 2025, 19 October 2025). To foster spiritual communion, I give you my blessing with this simple prayer:

Holy Father, make us one in Christ, rooted in his love that unites and renews. May all members of the Church be united in mission, docile to the Holy Spirit, courageous in bearing witness to the Gospel, proclaiming and daily embodying your faithful love for all creatures.

Bless all missionary men and women, support them in their efforts, and watch over them in hope!

Mary, Queen of Missions, accompany our work of evangelization in every corner of the Earth: make us instruments of peace, and grant that the whole world may recognize in Christ the light that saves. Amen.

LEO PP. XIV