“And when the day of Pentecost was fully come, they were all with one accord in one place.”
King James Version (KJV)
2:1 At the pentecost of Sinai, in the Old Testament, and the pentecost of Jerusalem, in the New, where the two grand manifestations of God, the legal and the evangelical; the one from the mountain, and the other from heaven; the terrible, and the merciful one. They were all with one accord in one place - So here was a conjunction of company, minds, and place; the whole hundred and twenty being present.
Ac 2:1 The Day of Pentecost SUMMARY OF ACTS 2: The Disciples Gathered Together. The Baptism of the Spirit. The Apostles Speak as the Spirit Gives Utterance. The Gospel Heard in Many Tongues. The Theory of the Scoffers. Peter's Sermon. The Prophecy of Joel Fulfilled. Christ and the Resurrection Preached. The Jews Convicted of Crucifying the Lord. The Inquiry of Convicted Sinners. Peter's Reply. Three Thousand Baptized. Continuing in the Apostles' Doctrine. The Progress of the Church. When the day of Pentecost was fully come. The entire period between it and the passover, the waiting period of the disciples, was filled full. Pentecost, one of the three great annual festivals of the Jews, lasted only one day, was on the fiftieth day from the morrow after the passover Sabbath (Le 23:15-22). The Savior, crucified on Friday, was in the tomb on the passover Sabbath, and rose on Sunday, the day from whence the count began. The Sunday following would be the eighth day, and the fiftieth day would fall on Sunday, the first day of the eighth week. Hence, the ancient church observed Pentecost on the first day of the week. For fuller discussion, see Meyer, Howson and Milligan on this passage. All agree that Pentecost come on Sunday. Pentecost was the feast of the grain harvest, and was also held by the Jews to be the anniversary of the giving of the law (Ex 23:16 34:22,23). They were all . . . in one place. Not only the apostles, but the hundred and twenty disciples. They probably had an intimation that the promised day had come.