Study The Church

The first year of Christianity: 3000 to 10,000

This summary looks at the very earliest church history. Our time period: the first year of Christianity. Jesus was crucified in the year AD 30, so we will look at the growth of Christianity from AD 30 to AD 31. The only source of information for that first year is the Bible itself, specifically the book of Acts, although other New Testament books add clues.

Acts begins with Jesus eating with his Apostles. He tells them to wait in Jerusalem until the Holy Spirit comes. (1:4,5) That would be his last direct order. The next few verses relates Jesus’ words as he tell the Apostles that they would be His witnesses “in Jerusalem, and in all Judea and Samaria, and to the ends of the earth.” (1:8) And then he ascended to heaven.

Before we go any further, let’s count the number of believers on earth as Jesus ascends to heaven. We have the eleven Apostles, with Judas having committed suicide, but is there anyone else? The books of Luke and I Corinthians add more. During the ministry of Jesus, he had the twelve Apostles plus he had seventy other guys. Luke describes how “the Lord appointed seventy [or maybe seventy-two] others and sent them two by two ahead of him to every town and place where he was about to go.” (Luke 10:1) So at the very beginning of Christianity (which I am defining as the moment Jesus ascended), the number of believers is eleven plus seventy.

But wait because there were others. In I Corinthians, Paul lists the people who saw the resurrected Jesus: “He appeared to Peter, and then to the Twelve. After that, he appeared to more than five hundred of the brothers at the same time .” (I Corinthians 15:5,6) So we have the Twelve (more on that later), the seventy (from Luke) and the 500 “brothers.” Even if we assume that the seventy were part of the 500, that leaves over 500 believers at the ascension of Jesus. And that was just the men. If we allow for an equal number of female believers the number is around 1000. So that is the figure at the moment church history starts.

Moving on. As soon as Jesus ascended to heaven, the Apostles went to Jerusalem to wait on the Holy Spirit, per Jesus’ last instructions. While they were waiting they decided to replace Judas with another Apostle. They decided the “it is necessary to choose one of the men who have been with us the whole time the Lord Jesus went in and out among us, beginning from John’s baptism to the time when Jesus was taken up from us.” (1:21,22) The man they chose was Matthias (1:26) and “so he was added to the eleven apostles.” Thus the Twelve mentioned by Paul in I Corinthians probably included Matthias.

Right after that, the Day of Pentecost occurred, when the Holy Spirit came on the Christians. When it happened Peter went out and preached and “about three thousand [men and women] were added to their number that day.” (2:41) So within a couple of months after Jesus’ ascension the number of Christians had increased to around 4000 believers.

They stayed in Jerusalem, for Acts 2:44 states “All the believers were together.” Then Peter healed a crippled man and preached to the amazed crowd. And some believed his message so that the “number of men grew to about five thousand.” (4:4). Again, we can double that in order to account for the female believers, so 10,000 believers. Now, we don’t know how much time passed between the Day of Pentecost (4000 believers) and the 10,000 believers because Acts 3:1 only states: “One day Peter and John were going up to the temple.” But we can assume that it was less than one year.

So there you have it: one year into Christianity, the believers had increased from around 1000 to 10,000. And almost 2000 years later, Christianity numbers around 2 billion believers.