Matthias is the apostle who was chosen after Jesus' ascension into heaven according to the Acts of the Apostles, ch. 1.

matthias_apostleAfter the ascension of Jesus into heaven and before the giving of the Holy Spirit on Pentecost, the band of disciples, which constitutes the body that will replace the body of Jesus that now is at the right hand of the Father in heaven, is suffering from a grave problem: there is a member missing. Jesus chose twelve disciples and he sent them out as apostles to do his works. At the time of his death, only eleven remained because Judas Iscariot had betrayed him, handing him over to the authorities. The damaged body must find its missing member before Jesus pours out his Spirit on it.

In chapter 1 of the Acts of the Apostles, the election of Matthias to fill the vacuum is retold. We know no further details about this apostle from the New Testament. Christian tradition tells that he went to evangelize Georgia (or perhaps Ethiopia) and died a martyr's death.

His feast in the contemporary Catholic Church is close to the Feast of the Ascension and before Pentecost.