Apostle

An apostle is, by definition, one sent out on a mission and is derived from the Greek word ἀπόστολος (apóstolos), which is a term given to the 12 companions of Jesus, noted in Mk. 3:13-19, whom he commissioned to proselytize his religious ideology and also whom he awarded the supernatural—authority to drive out les démons!

In Christianity, the term generally refers to the twelve disciples (students) of Jesus depicted in the New Testament of the Bible. They are often referred to in the Gospels and Acts of the Apostles as simply "the Twelve." See, for example, Mark 3:13-15. In order to keep their number at twelve, Matthias was chosen to replace Judas as an apostle in Acts 1:21-26. Paul called himself an apostle, and others as well, although he had never met Jesus (Gal. 2:8, Rom. 16:6-7).

The gospels are not consistent in their identification of the apostles. Gospel of Mark and Gospel of Matthew identify the twelve apostles as being Simon (AKA Peter), Andrew, James son of Zebedee, John son of Zebedee, Philip, Bartholomew, Thomas, Matthew (AKA Levi), James son of Alphaeus, Thaddaeus, Simon the Cananean, and Judas Iscariot (Mk. 3:14-19, Mt. 10:2-4). Gospel of Luke cites a similar list although identifies Judas son of James in place of Thaddaeus (Lk. 16:13-16). Gospel of John mentions only nine apostles by name, eight from the previous lists, Simon, Andrew, James son of Zebedee, John son of Zebedee, Philip, Thomas, Judas Iscariot, and Judas, in addition to adding Nathanael.

Peter

 * See main article: Peter the Apostle

The New Testament portrays the Apostle Peter as being the leader of the apostles and present at such events as various healings, resurrections, and other miracles performed by Jesus in addition to Jesus' transfiguration (Mk. 9:2-8), signs of the end of the age (Mk. 13), anguish at the garden (Mk. 14:32-42), empty tomb, and resurrection appearances. Peter is also mentioned in relation to several significant events in Acts.

Paul states that Peter was ordained by God as apostle to the Jews. If Peter was the same person as Cephas mentioned by Paul in Galatians 2:9 and various verses in First Corinthians, then he was someone of importance in the church and moreover known to Paul.

Peter is traditionally credited with authorship of First Peter and Second Peter and the apocryphal (non-canonical) Gospel of Peter and Apocalypse of Peter, although scholars deny the possibility of him having written any but the first.

Traditionally Peter served as the first bishop of Rome until his execution by crucifixion.

Non-New Testament references to Peter consist solely of documentation of oral tradition recorded long after his death.

Andrew
The Apostle Andrew was the first disciple recruited, along with his brother Peter (Mk. 1:16-18). Aside from a few insignificant instances of dialog, the only significant event that Andrew participated in was the signs of the end of the age. He is not mentioned in Acts aside from his identification as an apostle and is the subject of the apocryphal Acts of Andrew.

Traditionally Andrew founded the Patriarchate of Constantinople in about 38 CE and was martyred in the mid to late first century. He is the patron saint of Barbados, Romania, Russia, Scotland and Ukraine.

James son of Zebedee
The Apostle James, son of Zebedee, also known as James the Greater, was, obviously, the brother of John. Although he was present at many significant events in the gospels his only mention in Acts is when he was beheaded, in around 44 CE. Patron saint of Spain, he is venerated at Santiago de Compostela.

John son of Zebedee
The Apostle John, son of Zebedee, brother of James, was present at many New Testament events. He is presumed to be the same John mentioned by Paul as being a significant person in the early church (Gal. 2:9).

Although written anonymously, the Gospel of John and the three epistles bearing his name are traditionally attributed to John as is the apocryphal Apocalypse of John. Similarly tradition attributes authorship of the Book of Revelation, which claims to have been written by one named John (Rev. 1:9), to the Apostle John.

Tradition has it that John was placed in a cauldron of boiling oil and emerged uninjured. Per tradition he moved to Ephesus where he cared for Jesus' mother and lived to be around 100 years old. Alternatively, according to a quote from one Philip of Side, John the Apostle was "killed by the Jews" sometime before 70 CE.

Philip
The Apostle Philip's mention in the Bible is, aside from his introductions, limited to a few unhistorical events. Per the Acts of Philip (fourth century) Philip was crucified in about 80 CE.

Bartholomew
The Apostle Bartholomew is mentioned only four times in the Bible, in his introductions in Matthew, Mark, Luke, and Acts. Legends maintain both that Bartholomew was martyred in Armenia and in India as well, in about 62 CE, however there is archeological evidence for this event.

Thomas
The Apostle Thomas, also Didymus, also Judas or Jude, aside from his introductions and insignificant lines in Jesus' farewell discourse (John 11:16) and the unhistorical raising of Lazarus (John 14:5), appears in the Bible only in the famous doubting passage (John 20:24-29).

The apocryphal Gospel of Thomas and equally apocryphal Infancy Gospel of Thomas both claim in their introduction to have been written by Thomas, but almost certainly weren't - both are conventionally dated to the 2nd century CE. The pseudepigraphical (forged) and apocryphal Acts of Thomas was written in the first quarter of the third century.

Per tradition Thomas the Apostle was martyred in India, however, there is no archeological evidence of such a person visiting India.

Matthew
The Apostle Matthew, also Levi, appears in the Bible only in his calling and introductions in the Gospels. Although it was written anonymously, tradition gives Matthew authorship of the gospel with his name.

Some claim that Matthew the Apostle was martyred in Egypt by Alexandrian Sanhedrin.

James son of Alphaeus
The Apostle James, son of Alphaeus, is claimed to be the same as James the Just documented by early church historians as well as James the less mentioned in Mark 15:40. The Apostle James is claimed to be the same James mentioned by Paul as being a "pillar" in the early church (Gal. 2:9) and the "Lord's brother" (Gal. 1:19), although the latter association need not compel the belief that James was the literal brother of Jesus. The Jewish and Roman historian Josephus, writing around 94CE, mentions a James who was brother to Jesus (Flavius Josephus: Antiquities of the Jews, Book 20, Chapter 9, 1), though the date of this writing means it isn't necessarily independent of Christian sources.

James is noted to have witnessed the resurrected Jesus in a passage in which he is identified as distinct from the apostles (1 Cor. 15:7). James decrees that gentile Christians need not follow Jewish law in Acts 15:13-21, although this decree is not mentioned by Paul in parallel passages in chapter 2 in Galatians.

Surviving quotes from the Gospel of the Hebrews suggest James was a key figure in that lost work. James is first of the "seventy disciples," a third century list based on the reference in Luke 10:1.

James son of Alphaeus is traditionally understood to be the author of Epistle of James, who identifies himself only as James (James 1:1), although most scholars suspect this work to be a pseudepigraph.

Based on the identification as James the just, he is traditionally believed to be the first bishop of Jerusalem. Per tradition James the Apostle was stoned to death in about 62 CE.

Thaddaeus
The Apostle Thaddaeus is mentioned in the entire Bible only in his introductions in Matthew and Mark. In order to help reconcile the lists of apostles from various gospel writers, Thaddaeus is claimed by some to be the same person as Judas mentioned in Luke and John and as Jude of the Epistle of Jude.

Simon the Cananean
The Apostle Simon the Cananean, also Simon the Canaanite or the Zealot or Zelotes, appears in the Bible only in his introduction in Matthew, Mark, Luke, and Acts. Traditionally he was martyred with Judas, son of James.

Judas Iscariot

 * See main article: Judas Iscariot

The Apostle Judas (Iscariot) appears in all four gospels and in Acts as the character who betrayed Jesus. There are two conflicting accounts of his death in the Bible. According to Matthew, Judas hanged himself (Mt. 27:5), while in Acts, Judas falls in a field, spontaneously becoming disemboweled somehow (Acts 1:18).

The apocryphal Gospel of Judas was written between 130 and 170 CE and suggests that what's traditionally considered a betrayal of Jesus was in fact a part of Christ's plan, since humanity's sins could not otherwise be redeemed.

Judas son of James
The Apostle Judas, son of James, mentioned in Luke 6:16 and Acts 1:13 is believed also to be the same person referred to in John 14:22. Some say he is the same person as the Apostle Thaddaeus. Some say he is the same person as the author of the Epistle of Jude written 90 to 120 CE, which most scholars suspect to be a pseudepigraph.

Per tradition Judas son of James was martyred in Lebanon in about 65 CE.

Nathanael
The Apostle Nathaneal appears in the Bible only in the first chapter of John with one mention in the last as well. Some say he is the same person as the Apostle Bartholomew.

Mary Magdalene
Though typically thought of as a star-struck hanger-on "saved" from sex work by Christ, the evidence actually points to Mary having been a full-on disciple and church leader in her own right, whose character was somehow warped over time.

In the Gospel of Thomas, she is mentioned three times with nothing of note said to demonstrate how she is supposedly distinct from any of the other disciples. Some scholars and feminist writers have taken this face value; that she was simply one of the handful of Jesus’ students and that he accepted her without commentary. She also inspired her own Gospel of Mary, which (perhaps unsurprisingly) claims she was Jesus' most beloved disciple, and the Gospel of Philip further claims a sexual & marital relationship between her and the Saviour. Whilst one might dismiss these sources as apocryphal, Thomas is considered by most scholars to be as authentic about Jesus' words as Mark (the earliest of the Synoptic Gospels). More cynical readers might also suggest that Mary's lack of a penis may also have hindered her acceptance as both an apostle, church leader and non-prostitute.

Matthias
The Apostle Matthias is chosen to replace Judas in Acts 1:23-26 and is mentioned nowhere else in the Bible. The lost Gospel of Matthias, written 110 to 160 CE, is traditionally ascribed to Matthias. I found a website that said Matthias was possibly stoned in Jerusalem.

Paul

 * See main article: Paul of Tarsus

Although he considered himself an apostle, the Apostle Paul was not one of the Twelve Apostles. In fact he never met Jesus, having received his calling in a vision. However, Paul never indicated that having received his calling in this indirect manner made him any less worthy to preach the gospel.

Although Paul's letters, written in the 50's CE, are the earliest-written works in the New Testament, he never acknowledges a recent, historical Jesus within them. Of the 13 epistles attributed to Paul, scholars have concluded that seven were actually written by Paul and four are pseudepigraphical and they are undecided on the remaining two.

Traditionally Paul the Apostle was beheaded in Rome around 67 CE.

Acts of the Apostles
Acts was written for the purpose of demonstrating that the actions of Jesus' disciples following his execution justified preaching Christianity to the gentiles, although its historical accuracy is disputed. In addition it contains many internal inconsistencies and contradictions with other Bible books.

Conclusions
The number twelve seems to have been chosen for the apostles due to its significance in ancient Jewish culture. Aside from in reference to Peter (or Cephas), John, and a James, there is no evidence other than tradition and their mention in the New Testament that indicates the apostles existed.