Gospel (Mk 3,13-19) - At that time, Jesus went up the mountain, called to him those he wanted and they came to him. He appointed Twelve of them - whom he called apostles - to be with him and to send them to preach with the power to drive out demons. He therefore constituted the Twelve: Simon, to whom he gave the name of Peter, then James, son of Zebedee, and John, brother of James, to whom he gave the name of Boanèrghes, that is, "sons of thunder"; and Andrew, Philip, Bartholomew, Matthew, Thomas, James, son of Alphaeus, Thaddaeus, Simon the Canaanite, and Judas Iscariot, who then betrayed him.

The commentary on the Gospel by Monsignor Vincenzo Paglia

After welcoming the crowds on the shores of the lake, Jesus moves to a mountain. The mountain is the place of prayer, the place of encounter with God, rather than of mission among people. And Jesus, writes Mark, "called to him those he wanted and they went to him". It is he who chooses them and calls them. After accepting the call, Jesus takes them with him. There are twelve, like the twelve tribes of Israel. Finally the entire people of God found their unity around the one shepherd. Those Twelve are united starting from Jesus who called them and associated them with his same mission. It is the Lord who keeps them united as brothers, nothing else. The reason for Christian communion is Jesus alone, certainly not nationality, common interests, cultural or blood ties, common condition or belonging. The only thing that unites them is that they are all disciples of that one master. But being close to Jesus is not meant to close oneself in an elitist group, worried about one's life. Jesus "constituted" them, that is, he established them in unity, not so that they would remain among themselves, but so that they would be sent "to preach, with the power to cast out demons". This is precisely what Jesus himself did: preach the kingdom of God and cast out demons. The Church, founded on the Twelve, is called to continue this same work throughout the centuries and throughout the world. The Christian community is not an anonymous people, made up of people who have no ties to each other. The Lord called the Twelve by name, one by one. Thus was born the first community of the Twelve. And in the same way every Christian community continues to arise today. Each has its own name, its own story. And everyone is entrusted with the mission of announcing the Gospel and healing illnesses. The condition prior to the mission is to be "with Jesus". It could be said that the apostle is first of all a disciple, that is, someone who is with Jesus, who listens to him, who follows him.