Then they returned to Jerusalem from the Mount of Olives, which is near Jerusalem—a sabbath day’s journey away. When they entered the city, they went to the upstairs room where they were staying. Peter, John, James, and Andrew; Philip and Thomas; Bartholomew and Matthew; James, Alphaeus’ son; Simon the zealot; and Judas, James’ son— all were united in their devotion to prayer, along with some women, including Mary the mother of Jesus, and his brothers.
During this time, the family of believers was a company of about one hundred twenty persons. Peter stood among them and said, “Brothers and sisters, the scripture that the Holy Spirit announced beforehand through David had to be fulfilled. This was the scripture concerning Judas, who became a guide for those who arrested Jesus. This happened even though he was one of us and received a share of this ministry.”
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“Therefore, we must select one of those who have accompanied us during the whole time the Lord Jesus lived among us, beginning from the baptism of John until the day when Jesus was taken from us. This person must become along with us a witness to his resurrection.” So they nominated two: Joseph called Barsabbas, who was also known as Justus, and Matthias.
They prayed, “Lord, you know everyone’s deepest thoughts and desires. Show us clearly which one you have chosen from among these two to take the place of this ministry and apostleship, from which Judas turned away to go to his own place.” When they cast lots, the lot fell on Matthias. He was added to the eleven apostles.
Acts 1:12-17, 21-26