28 October 2020 Catholic Mass Daily Bible Reading.

USCCB. Holy Gospel of Jesus Christ according to Saint Luke 6,12-16.
Jesus departed to the mountain to pray, and he spent the night in prayer to God.
When day came, he called his disciples to himself, and from them he chose Twelve, whom he also named apostles:
Simon, whom he named Peter, and his brother Andrew, James, John, Philip, Bartholomew,
Matthew, Thomas, James the son of Alphaeus, Simon who was called a Zealot,
and Judas the son of James, and Judas Iscariot, who became a traitor.

Copyright © Confraternity of Christian Doctrine, USCCB

Benedict XVI
pope from 2005 to 2013
General Audience of 03/05/2006 (©Libreria Editrice Vaticana)

"He called his disciples to himself, and from them he chose Twelve, whom he also named apostles"
The apostolic Tradition is not a collection of things or words, like a box of dead things. Tradition is the river of new life that flows from the origins, from Christ down to us, and makes us participate in God's history with humanity. This topic of Tradition (…) is of great importance for the life of the Church. The Second Vatican Council pointed out in this regard that Tradition is primarily apostolic in its origins: "God graciously arranged that the things he had once revealed for the salvation of all peoples should remain in their entirety, throughout the ages, and be transmitted to all generations. Therefore, Christ the Lord, in whom the entire Revelation of the Most High God is summed up (2 Cor 1:20; and 3:16-4, 6), commanded the Apostles to preach the Gospel and communicate the gifts of God to all men. This Gospel was to be the source of all saving truth and moral discipline" (Dogmatic Constitution on Divine Revelation 'Dei Verbum', n. 7). The Council noted further that this was faithfully done "by the Apostles who handed on, by the spoken word of their preaching, by the example they gave, by the institutions they established, what they themselves had received - whether from the lips of Christ, from his way of life and his works, or whether they had learned it at the prompting of the Holy Spirit" The Council adds that there were "other men associated with the Apostles, who, under the inspiration of the same Holy Spirit, committed the message of salvation to writing".
As heads of the eschatological Israel, and likewise as Twelve, the number of the tribes of the Chosen People, the Apostles continued the "gathering" begun by the Lord and did so first and foremost by transmitting faithfully the gift received, the Good News of the Kingdom that came to people in Jesus Christ. Their number not only expresses continuity with the holy root, the Israel of the twelve tribes, but also the universal destination of their ministry, which brought salvation to the very ends of the earth. This can be understood from the symbolic value that the numbers have in the Semitic world: twelve results from the multiplication of three, a perfect number, and four, a number that refers to the four cardinal points, hence, to the whole world.