Matthias 

Originally, there were twelve apostles, but Judas Iscariot killed himself after betraying Jesus. Jesus was crucified, then resurrected, and appeared before the remaining eleven apostles on several occasions. After Jesus’ farewell appearance, Peter called a meeting of his fellows and the leading disciples. They met at the same place where the Last Supper was enacted, the Upper Room of the Mark house. At the end of this meeting, Peter told those gathered that the apostles had decided to choose a successor to Judas, and that two devoted followers of Jesus had been nominated to fill this position, Matthias and Justus.The eleven apostles then went downstairs to pray and vote to determine which of these men would serve as their treasurer. The vote was for Matthias, and he was duly appointed to that office. The apostles then returned to the Upper Room to announce the choice. Matthias had little part in the subsequent activities of the apostles. Aside from this brief episode, he is not cited again.

After Judas took his own life (Acts 1:18, Matthew 27:5), the office of treasurer of the apostles was left open until Jesus ascended. The New Testament (Acts 1:21-26), states that Matthias and Justus (also known as Joseph Barsabas) were followers of Jesus from the times when John the Baptist was still alive. When those two were suggested as replacements for Judas, the apostles prayed to know which one to select. They then voted and Matthias won. He was then counted as an apostle, one of twelve. No more is said about him in the Biblical record, either before or after being chosen as Judas’ replacement

Although Matthias appears only briefly in the Bible, he was sainted and named as the author of an apocryphal gospel. Only fragments of the so-called Gospel of Matthias exist, and early church fathers dismissed it as second century heretical writings. Matthias’ gospel is cited in works by early Christian historians, Clement of Alexandria, Origen, Eusebius, and others.

The feast of Saint Matthias was included in the Roman Calendar in the 11th century and celebrated on February 24th, later moved to May 14th. The Eastern Orthodox Church celebrates his feast day on August 9th. Various other faith traditions use one or more of those dates.

It is claimed that the remains of Matthias were brought to Italy through Empress Helena, mother of Emperor Constantine I (the Great). Part of these relics would be interred in the Abbey of Santa Giustina at Padua and the remaining in the Abbey of St. Matthias, Trier, Germany. According to Greek sources, the remains of Matthias are buried in the castle of Gonio-Apsaros, Georgia.