The Church Age is the total length of time from the beginning of the New Testament Church until God instantaneously takes the Church out of the world. The beginning day of this Age was on the 50th day after the Lord Jesus was resurrected back to life from the dead. It is vitally important to remember—Christ was raised on the first day of the week—and then fifty days later, the Holy Spirit came to begin the Church—also on the first day of the week—Pentecost.
When the Day of Pentecost had fully come, they were all with one accord in one place. And suddenly there came a sound from heaven, as of a rushing mighty wind, and it filled the whole house where they were sitting.