Acts 1:1-3 The former treatise have I made, O Theophilus, of all that Jesus began both to do and teach, [including revealing Himself in His resurrection form] Until the day in which He was taken up [Ascension - 40 days after the resurrection of Jesus and ten days before Pentecost], after that He (Jesus) through the Holy Ghost had given commandments unto the Apostles whom He had chosen: To whom also He shewed Himself alive after [Holy Week] His passion by many infallible proofs, being seen of them (Apostles) forty days, and speaking of the things pertaining to the Kingdom of God:
Acts 2:40-43 And with many other words did he [Apostle Peter] testify and exhort, saying, Save yourselves from this untoward generation. Then they [common Christians] that gladly received his word were baptized: and the same day [Pentecost] there were added unto them [Christian Church] about three thousand souls. And they [common Christians] continued stedfastly in the Apostles' doctrine and fellowship, and in breaking of bread, and in prayers. And fear came upon every soul: and many wonders and signs were done by the Apostles.
Romans 16:7 Salute Andronicus and Junia [1 Corinthians 15:6 - fellow Jews (a husband and wife) who had also witnessed the resurrection of Jesus back in Jerusalem], my kinsmen, and my fellowprisoners, who are of note among the Apostles, who also were in Christ before me [Apostle Paul].
1 Corinthians 15:1-11 Moreover, brethren, I declare unto you the Gospel which I preached unto you, which also ye have received, and wherein ye stand; By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain. For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures; And that He was buried, and that He rose again the third day according to the scriptures: And that He was seen of Cephas [Apostle Peter], then of the Twelve: After that, He was seen of above five hundred brethren at once; of whom the greater part remain unto this present, but some are fallen asleep. After that, He was seen of James; then of all the Apostles. And last of all He was seen of me [Apostle Paul] also, as of one born out of due time [outside the 40 resurrection days of the Apostolic Era]. For I am the least of the apostles, that am not meet to be called an apostle, because I persecuted the church of God. But by the grace of God I am what I am: and His grace which was bestowed upon me was not in vain; but I laboured more abundantly than they all: yet not I, but the grace of God which was with me. Therefore whether it were I or they, so we preach, and so ye believed.
Ephesians 2:19-22 Now therefore ye are no more strangers and foreigners, but fellow citizens with the saints, and of the Household of God; And are built upon the foundation of the [N.T.] Apostles and [O.T.] Prophets, Jesus Christ himself being the chief corner stone; In whom all the building fitly framed together groweth unto an Holy Temple in the Lord: In whom ye also are builded together for an habitation of God through the [Holy] Spirit.
The Apostles Era was initiated during the 40 days that the resurrected Jesus revealed Himself to mankind. In order to be a Biblical Apostle of the Apostolic Era a person would have to have personally witness the bodily Resurrection life of Jesus Christ and then would have gone out and proclaimed to others the “Gospel” the Good News of the Resurrection of Jesus Christ.
Today Christians are “sent out” as an apostle but it is via their Witness of the Holy Spirit and not from a direct bodily encounter with the Resurrected Jesus Christ that the original Apostles had encountered.
One of the more interesting aspects of looking at the lives of the Apostles is just how much each of their individual lives changed and it changed primarily from their outlook from being socially [worldly, societally] aware to becoming Kingdom aware and eternally aware in Jesus Christ.
The change among each individual Apostle seems to have been huge as it encompassed their personalities, individual behavior and individual outlook on life and in fact the very meaning of life itself for each of them. Therefore the majority of the Biblical writings of the Apostles is directed at a certain amount of expected godly behavior modification, in a good way i.e. removing doubt, uncertainty and fear, in the lives of each new Christian convert.
The first Church Council of Apostles and Elders in Jerusalem offered four behavior modification agendas to the new Gentile Christian converts.
The Church Creeds [Jerusalem, Nicene, etc.] are important and relevant to all of Christianity. The Jerusalem Creed [1st Church Council about 49 A.D. in Jerusalem] has 4 Cornerstones. "Acts 1:20-21 [The Jerusalem Creed - 1st Church Council about 49 A.D. in Jerusalem] But that we [Apostles] write unto them [Gentile Christians], (1.) that they abstain from [occult] pollutions of idols, (2.) and from [immorality] fornication, (3.) and from things [cruelty] strangled, (4.) and from [Levitical] blood. **For Moses of old time hath [traditional Jews] in every city them that preach him (Moses), being read in the synagogues every Sabbath day" the fourth one being not to offend traditional Jews. Since one of the Cornerstones of the 1st Church Council is to support Jews and Traditional Judaism it is an original and longstanding tenant that true Christianity acknowledges its debt and emergence from (God ordained) Mosaic Judaism.
But by the time the Christian Church matured into the later Church Councils (i.e. Council of Nicaea in 325 A.D.) the majority of the entire Church Council was no longer about individual Christian behavior modification but instead became vested, almost exclusively, in individual Christian though, knowledge and doctrine. This later Christian Pastoral emphasis on individual Christian thought (i.e. think as I do) has continued on until the present modern Church day.
Though now Pastor Rick Warren and many others are dramatically shifting the current Christian Church away from thought, creeds and doctrines and are again shifting the Christian Church back into the realm of behavior modification but disastrously it is not a return to the original behavior modification and godly accountability the Church Apostles sought for each Christian convert it is instead a behavior modification that is directing each individual away from Christianity and back into the abyss of the world specifically the very spiritually dangerous occult and pagan world.
Note: The first generation or two of Church leaders, bishops and writers after the Apostles are known as the "Church Fathers" [i.e. Irenaeus] and apparently if they were actually a disciple of one of the Apostles [i.e. Papias (70-163 A.D.) and Saint Polycarp (69-155 A.D.)] they instead were called an "Apostolic Father."
Source: blog History Study