Matthias was the apostle chosen to replace Judas after he betrayed Jesus and committed suicide. He was chosen by casting lots after Jesus reportedly ascended to heaven. The choosing of Matthias is depicted in the first chapter of Acts 1:15-26.
“At one point during those days (following the Ascension of Jesus), Peter stood up in the center of the brothers; there must have been a hundred and twenty gathered together. ‘Brothers,’ he said, ‘the saying in Scripture uttered long ago by the Holy Spirit through the mouth of David was destined to be fulfilled in Judas, the one who guided those that arrested Jesus. He was one of our number and he had been given a share in this ministry of ours.
That individual bought a piece of land with his unjust gains, and fell headlong upon it. His body burst wide open, all his entrails spilling out. This event came to be known by the inhabitants of Jerusalem, who named the property, Field of Blood.
It is written in the Book of Psalms, ‘Let his encampment be desolate. May no one dwell on it.’ And again, ‘May another take his office’.
It is entirely fitting, therefore, that one of those who was of our company while the Lord Jesus moved among us, from the baptism of John until the day he was taken up from us, would be named as witness with us to his resurrection.
At that they nominated two, Joseph (called Barsabbas, also known as Justus) and Matthias. Then they prayed 'O Lord, you read the hearts of men. Make known to us which of these two you choose for this apostolic ministry, replacing Judas, who deserted the cause and went the way he was destined to go'. They then drew lots between the two men. They choice fell to Matthias, who was added to the eleven apostles.”
St. Peter declared that the choice for a new apostle should fall upon someone who was a witness to the resurrection of Jesus. Apparently Matthias fit that reason. Other than this one mention of him in Acts, there is no further written information regarding what he did after that. We hear mostly of those who came in contact with Paul, who wrote so extensively.
