'Day of Pentecost' in the Bible

And when the day of Pentecost was fully come, they were all with one accord in one place.

"And while I was speaking, [the power of] the Holy Spirit descended on them [i.e., Cornelius' Gentile household] just like [it fell] on us [Jewish apostles] at the beginning [i.e., the day of Pentecost, See chapter 2].

For Paul had determined to sail by Ephesus, because he would not spend the time in Asia: for he hasted, if it were possible for him, to be at Jerusalem the day of Pentecost.

But I will wait [here] in Ephesus until the Day of Pentecost [Note: This was an annual Jewish festival, held at spring harvest time];