Who Attended The 'Birthday Of The Church'?
What some call the "birthday of the Church" happened on Pentecost (see Calendar of Christ's Holy Days; listen also to the Sermon Pentecost, A Day Of Reckoning). The Holy Spirit of God is what makes a Christian.
"2:1 And when the day of Pentecost was fully come, they were all with one accord in one place. 2:2 And suddenly there came a sound from heaven as of a rushing mighty wind, and it filled all the house where they were sitting. 2:3 And there appeared unto them cloven tongues like as of fire, and it sat upon each of them. 2:4 And they were all filled with the Holy Ghost, and began to speak with other tongues [see The Origin Of Speaking In Tongues], as the Spirit gave them utterance." (Acts 2:1-4 KJV)
"Jews, devout men, out of every nation under heaven"
Notice carefully who those first Christians were: "Jews, devout men, out of every nation under heaven." The people of Judah had been widely scattered over the entire known world, the Roman Empire (see also Paul's World). They were so firmly rooted in those other lands that they called the foreign languages of all of those places their own native language i.e. "heard them speak in his own language" ... "wherein we were born." That "birthday of the Church" Pentecost involved mostly believing Jews, not gentiles.
"2:5 And there were dwelling at Jerusalem Jews, devout men, out of every nation under heaven.
Peter was the apostle to the people of Judah, the "Jews." When he addressed the people at that "birthday of the Church," he recognized them as, and spoke to them as, Jews i.e. "Ye men of Judaea"
"2:14 But Peter, standing up with the eleven, lifted up his voice, and said unto them, Ye men of Judaea, and all ye that dwell at Jerusalem, be this known unto you, and hearken to my words: 2:15 For these are not drunken, as ye suppose, seeing it is but the third hour of the day. 2:16 But this is that which was spoken by the prophet Joel;
Despite the work of Peter having been successful (see also Peter's Prophecy), his was a limited success. Why? The answer is provided by the apostle Paul, also a Jew, who later led the "birthday of the Church" for the gentiles.
"11:13 For I speak to you Gentiles, inasmuch as I am the apostle of the Gentiles" 11:25 For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fulness of the Gentiles be come in. 11:26 And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob: 11:27 For this is my covenant unto them, when I shall take away their sins." (Romans 11:13-27 KJV)
Fact Finder: Were Peter and Paul very independent, of each other, while at the same time totally unified in their service to Christ?