Chosen by Jesus after He  prayed all night (Luke 6:12-16)  12  And it came to pass in those days, that he went out into a mountain to pray, and continued all night in prayer to God.  13  And when it was day, he called unto him his disciples: and of them he chose twelve, whom also he named apostles;  14 Simon, (whom he also named Peter,) and Andrew his brother, James and John, Philip and Bartholomew, 15 Matthew and Thomas, James the son of Alphaeus, and Simon called Zelotes, 16 And Judas the brother of James, and Judas Iscariot, which also was the traitor. 

   In these verses, we have the Lord Jesus in secret and in his family acting like himself.  The Twelve included two sets of fishermen brothers, a tax collector, and a traitor.  Among the Twelve, Peter, James, and John were particularly close to the Master.

   The termss disciple and apostle are often used interchangeably in referring to these men.  But a disciple is a learner or follower, while an apostle generally refers to a person who is sent with a special message or commission (John 13:16)  Truly, truly, I say to you, a servant is not greater than his master; nor is he who is sent greater than he who sent him.  The Twelve were definitely apostles; when Jesus called them, He had a specific mission in mind for them--to carry on His work after He ended His earthly mimistry.

    The original twelve were chosen from among those people whom Jesus knew personally (Acts 1:21, 22) So one of the men who have accompanied us during all the time that the Lord Jesus went in and out among us. 22 beginning from the baptism  of John until the day when he was taken up from us--one of these men must become with us a witness to his resurrection." They had an inadequate understanding of Jesus' mission and the necessity for His death (Matthew 15:16)  And Jesus said, Are ye also yet without understanding?.  Jesus was patient with the immature apostles, although He occassionally rebuked them (Luke 9:55) But he turned and rebuked them.  After they were empowered by the Holy Spirit at Pentecost, the apostles were filled with new boldness and understanding.  They became powerful witnesses in Jerusalem and surrounding regions, in spite of harsh persecution.  Many were martyred for their faith. 

   As listed in Matthew (10:1-4 And he called to him his twelve disciples and gave them authority over unclean spirits, to cast them out, and to heal every disease and every infirmity.  (2) The names of the twelve apostles are these: first, Simon, who is called Peter, and Andrew his brother; James the son of Zeebedee, and John his brother; (3) Philip and Bartholomew; Thomas and Matthew the tax collector; James the son of Alphaeus, and Thaddaeus;  Mark 3:13-19   And he went up on the mountain, and called to him those whom he desired; and they came to him.  14 And he appointed twelve, to be with him, and to be sent out to preach  15  and have authority to cast out demons:  16  Simon whom he surnamed Peter;  17 James the son of Zebedee and John the brother of James, whom he surnamed Bo-aner'ges, that is, sons of thunder;  18 Andrew, and Philip, and Bartholomew, and Mathew, and Thomas, and James the son of Alphaeus, and Thaddaeus, and Simon the Cananaean,  19 and Judas Iscariot, who betrayed him.  THen he went home; Luke 6:12-16; Acts 1:13  and when they had entered, they went up to the upper room, where they were staying,, Peter and John and James and Andrew, Philip and THomas, Bartholomew and Matthew, James the son of Alphaeus and Simon the Zealot and Judas the son of James.), The Twelve were: (1) Simon Peter (Cephas), leader of the apostles; (2) Andrew, brother of Simon; (3) James, son of Zebedee and brother John; (4) John, the beloved apostle; (5) Philip, from Bethsaida; (6) Bartholomew (probably Nathanael), from Cana of Galilee; (7) Matthew (Levi), tax collector; (8) Thomas (Didymus, which means "Twin"), from Galilee; (9) Simon the Canaanite, probably Simon the Zealot, from Galilee; (10) James, the son of Alphaeus; (11) Lebbaeus, or Thaddaeus; and (12) Judas Iscariot, who betrayed Jesus.

  Matthias was chosen by the apostles to replace Judas after the ascension of Jesus (Acts 1:26  And they cast lots for them, and the lot fell on Matthias; and he was enrolled with the eleven apostles).