APOSTLE - 1) Literally, "one who is sent." Apostle is used as a title for the Twelve Disciples who formed the foundation of the NT Church, replacing, symbolically, the twelve tribes of Israel. In order to maintain this symbolism, Matthias was elected to replace Judas (Acts 1:15 26). The word is also used of the Seventy (or 72) sent by Christ, as well as of Paul, the repentant persecutor whom the risen Jesus sent as "apostle to the Gentiles" (Rom. 11:13). Great missionaries in the Church, such as Mary Magdalene (the "apostle to the apostles"), Thekla, Nira, Vladimir, and Innocent of Alaska are called "equal to the apostles."? The extension of the apostolic ministry in the Church today is in the episcopacy.
The choosing of the twelve is recorded in Matthew 10:1-4 and Luke 6:12-16. The names of the twelve Apostles were: Simon, who is called Peter, and Andrew his brother; James and John the sons of Zebedee, Philip and Bartholemew, Thomas, Matthew the publican, James the son of Alpheus, Simon called the Zealot, Jude the brother of James (in the Gospel of Matthew listed as Thaddeus), and Judas Iscariot, who also was the traitor. After the Ascension of our Lord the Apostles chose Matthias to take the place of Judas Iscariot (ACTS 1:13-26). Later the name of Paul was added to the list of Apostles. Paul had persecuted the Christians until Our Lord appeared to him (ACTS 9) and called him to be an Apostle (ROM. 1:1, II COR. 1:1, GAL. 1:1).
Some saints who propagated the Christian faith are called Equal-to-the-Apostes, like St. Vladimir and Ss. Cyril and Methodius, who brought Christianity to the Slavs.
2) (an appellation or Title of Jesus) "Wherefore, holy brethren, partakers of the heavenly calling, consider the Apostle and High Priest of our profession, Christ Jesus;" Heb 3:1