The twelve apostles were called by Jesus; he identified their purpose, what they were to be doing, would do and did do. These men were with Christ “from the beginning.” They had been present at his baptism and through his ascension (with the exception of the betrayer — who gave up his hope). They were certainly religious men, of that there can be no doubt, and that would include Judas Iscariot. It would be incongruous to believe The Son of God somehow made religious men out of louts. They were Jews who lived and honored God everyday as must be inferred.
The list of the first twelve names is given in four places in the New Testament. The first three of these are in the gospel records attributed to Matthew, Mark and Luke. The fourth is found in the first chapter of the book of the Acts of Apostles.
Matthew 9: 1- 4:
And when He had called His twelve disciples to Him, He gave them power over unclean spirits, to cast them out, and to heal all kinds of sickness and all kinds of disease. Now the names of the twelve apostles are these: first, Simon, who is called Peter, and Andrew his brother; James the son of Zebedee, and John his brother; Philip and Bartholomew; Thomas and Matthew the tax collector; James the son of Alphaeus, and Lebbaeus, whose surname was Thaddaeus; Simon the Canaanite, and Judas Iscariot, who also betrayed Him.
Mark 3:16 — 19:
Simon, to whom He gave the name Peter; James the son of Zebedee and John the brother of James, to whom He gave the name Boanerges, that is, “Sons of Thunder”; Andrew, Philip, Bartholomew, Matthew, Thomas, James the son of Alphaeus, Thaddaeus, Simon the Canaanite; and Judas Iscariot…
Luke 6:13 — 16:
And when it was day, He called His disciples to Him; and from them He chose twelve whom He also named apostles: Simon, whom He also named Peter, and Andrew his brother; James and John; Philip and Bartholomew; Matthew and Thomas; James the son of Alphaeus, and Simon called the Zealot; Judas the son of James, and Judas Iscariot who also became a traitor.
And when they had entered, they went up into the upper room where they were staying: Peter, James, John, and Andrew; Philip and Thomas; Bartholomew and Matthew; James the son of Alphaeus, and Simon the Zealot; and Judas the son of James.
All are easily discernable names excepting Lebbaeus, once listed as having the surname Thaddaeus, and who apparently went by the common name of Judas, or Jude in its Greek form. This is disputed by linguists and scholars who note that Lebbaeus and Thaddaeus are common iterations of the same name. That would force that a scribal error was appended to Luke’s record and that the name may have been simply Thaddaeus.
Thaddaeus was the son of James (called by some, “the less”). James is listed as the son of Alphaeus (another common name), and is also once given as the brother of Matthew (Mark 2:14) making for more complications. While it seems likely that Judas and Matthew were not brothers or perhaps not even kinsman, Judas and James may have been father and son.
Peter and Andrew were brothers, and the two sons of Zebedee — James and John also, and that would form the third set of near relations, if James and Jude were related as stated, regardless of any relation to Matthew. Then a majority of the apostles (at least one-half) had family relationships within that tight circle. That should not come as a surprise. As Andrew brought Peter to Christ so the associations commence in kind. Brother brought brother to the Lord, Father brought son, mother brought daughter and son, kinsman brought kinsman, and friend brought friend.