Matthias was the one upon whom the lot fell when he, along with Joseph Barsabbas, was put forward to fill up the place in the apostleship left vacant by Judas Iscariot (Acts 1:15-26). This election was held at Jerusalem, and the meeting was presided over by Peter. The conditions demanded of the candidates were that they should "have companied with us all the time that the Lord Jesus went in and went out among us, beginning from the baptism of John, unto the day that he was received up from us," and that the one chosen should "become a witness with us of his resurrection" (Acts 1:21,22). The mode of procedure was by lot, and with prayer was the election made (compare Acts 1:24).

Hilgenfeld identifies Matthias with Nathanael (compare NATHANAEL). He was traditionally the author of the "Gospel of Matthias," a heretical work referred to by Origen (Hom. on Lk, i), by Eusebius (Historia Ecclesiastica, III, 25, 6) and by Hieronymus (Proem in Matth.). No trace of it is left. The Gnostic Basilides (circa 133 AD) and his son Isidor claimed to ground their doctrine in the "Gospel of Basilides" on the teaching Matthias received directly from the Saviour (Hippol., vii.20) (compare Hennecke, Neutestamentliche Apokryphen, 167). Various parts of the apocryphal "Contendings of the Apostles" deal with the imprisonment and blinding of Matthias by the Ethiopian cannibals, and his rescue by Andrew (compare Budge, Contendings of the Apostles, II, 163, 164, 267-88; see also ANDREW). According to the Martyrdom of Matthias (Budge, II, 289-94) he was sent to Damascus, and died at Phalaeon, a city of Judea. Other sources mention Jerusalem as the place of Matthias' ministry and burial.