The Greek word "Apostolos"
From “apo” meaning “away from” and “stello”, to “set in order”, to “prepare”.“Apostello” means “to send forth”, and “Apostolos” means the “one who is sent”.
“Apostolos” is used three ways in the NT:
1. In a broad sense, for any “messenger”:
--- 2 Corinthians 8:23 “Whether any do enquire of Titus, he is my partner and fellowhelper concerning you: or our brethren be enquired of, they are the messengers <652> (apostolos) of the churches, and the glory of Christ”.
--- Philippians 2:25 “Yet I supposed it necessary to send to you Epaphroditus, my brother, and companion in labour, and fellowsoldier, but your messenger <652>, (apostolos) and he that ministered to my wants”.
2. For anyone who is “sent”:
--- John 13:16 "Verily, verily, I say unto you, The servant is not greater than his lord; neither he that is sent <652> (apostolos) greater than he that sent him".
--- Barnabas was "sent" along with Paul:
Acts 14:14 “Which when the apostles <652>, Barnabas and Paul, heard of, they rent their clothes, and ran in among the people, crying out”.
Acts 13:1 Who was “Barnabas”? Barnabas was a prophet and teacher at Antioch:
“Now there were in the church that was at Antioch certain prophets and teachers; as Barnabas, and Simeon”
Acts 13:2-4 Paul and Barnabas were “SENT” forth by God and the other Apostles:
2. “As they ministered to the Lord, and fasted, the Holy Ghost said, Separate me Barnabas and Saul for the work whereunto I have called them.
3 And when they had fasted and prayed, and laid their hands on them, they sentthem away.
4 So they, being sent forth by the Holy Ghost, departed unto Seleucia; and from thence they sailed to Cyprus”.
Barnabas was only an “apostle” in the sense that he was “sent” to go with Paul.
3. The TWELVE APOSTLES OF THE LAMB:
We know there are only 12 "Apostles of the Lamb" and warnings against others who would call themselves "apostles".
--- Luke 6:13 “And when it was day, he called unto him his disciples: and of them he chose twelve, whom also he named apostles”.
--- Matthew 10:2 “Now the names of the(Greek article “the”) twelve apostles are these”. (A “Title”)
--- Luke 22:14 “And when the hour was come, he sat down, and the(Greek article “the”) twelve apostles with him.” (A “Title”)
--- Revelation 21:14 “And the wall of the city had twelve foundations, and in them the names of the(Greek article “the”) twelve apostlesof the Lamb.”
Warnings against False “Apostles”:
--- 2 Corinthians 11:13 “For such are false apostles, deceitful workers, transforming themselves into the apostles of Christ.”
--- Revelation 2:2 “I know thy works, and thy labour, and thy patience, and how thou canst not bear them which are evil: and thou hast tried them which say they are apostles, and are not, and hast found them liars:”
Paul, the Twelfth Apostle:
Personally, I believe Paul was chosen by Jesus Christ Himself to replace Judas. “Matthias” was picked by Peter and the eleven apostles, in their ignorance, and we never hear another word about him.
In Acts 9:15, The Lord told Ananias about Paul: “But the Lord said unto him, Go thy way: for he is a chosen vessel unto me, to bear my name before the Gentiles, and kings, and the children of Israel”. (Paul was “chosen” by Jesus, and “prepared” for 3 years by Jesus, and “sent” to Gentiles, and kings, and the children of Israel.)
Gal 1:1 “Paul, an apostle, not of men, neither by man, but by Jesus Christ, and God the Father, who raised him from the dead;”
In 2 Cor 12:11-12, Paul says - “I am become a fool in glorying; ye have compelled me: for I ought to have been commended of you: for in nothing am I behind the very chiefest apostles, though I be nothing.
12 Truly the signs of an apostle were wrought among you in all patience, in signs, and wonders, and mighty deeds.
I fully expect Paul’s name to be listed on the twelve foundations of the New Jerusalem.