Acts 2:1

When the day of Pentecost had come, they were all together in one place.

Acts 20:16

For Paul had decided to sail past Ephesus, so that he would not have to spend time in Asia; for he was hurrying to be in Jerusalem, if possible, on the day of Pentecost.

1 Corinthians 16:8

But I will stay in Ephesus until Pentecost,

Acts 1:13-15

And when they had entered, they went up to the upper room, where they were staying; Peter and John and James and Andrew, Philip and Thomas, Bartholomew and Matthew, James the son of Alphaeus and Simon the Zealot and Judas the son of James.

Acts 2:46

And day by day, attending the temple together and breaking bread in their homes, they ate together with glad and sincere hearts,

Acts 4:24

And when they heard this, they lifted their voices to God together and said, "Sovereign Lord, it is you who made the heaven and the earth and the sea, and everything in them,

Acts 4:32

Now the company of those who believed were of one heart and soul, and no one claimed that any of the things which he possessed was his own, but they had everything in common.

Acts 5:12

Now many signs and wonders were done among the people by the hands of the apostles. And they were all together in Solomon's Porch.

Romans 15:6

that you may with one mind and one mouth glorify the God and Father of our Lord Jesus Christ.

Philippians 1:27

Only conduct yourselves in a manner worthy of the gospel of Christ, so that whether I come and see you or remain absent, I will hear of you that you stand firm in one spirit, with one mind striving together for the faith of the gospel,

Philippians 2:2

make my joy complete by being of the same mind, having the same love, being one in spirit and purpose.

Treasury of Scripture Knowledge

Summary

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

General references

Bible References

The day

Acts 20:16
For Paul had decided to sail past Ephesus, so that he would not have to spend time in Asia; for he was hurrying to be in Jerusalem, if possible, on the day of Pentecost.
1 Corinthians 16:8
But I will stay in Ephesus until Pentecost,

They

Acts 2:46
And day by day, attending the temple together and breaking bread in their homes, they ate together with glad and sincere hearts,
Acts 1:13
And when they had entered, they went up to the upper room, where they were staying; Peter and John and James and Andrew, Philip and Thomas, Bartholomew and Matthew, James the son of Alphaeus and Simon the Zealot and Judas the son of James.
Acts 4:24
And when they heard this, they lifted their voices to God together and said, "Sovereign Lord, it is you who made the heaven and the earth and the sea, and everything in them,
Acts 5:12
Now many signs and wonders were done among the people by the hands of the apostles. And they were all together in Solomon's Porch.
Romans 15:6
that you may with one mind and one mouth glorify the God and Father of our Lord Jesus Christ.
Philippians 1:27
Only conduct yourselves in a manner worthy of the gospel of Christ, so that whether I come and see you or remain absent, I will hear of you that you stand firm in one spirit, with one mind striving together for the faith of the gospel,
Philippians 2:2
make my joy complete by being of the same mind, having the same love, being one in spirit and purpose.

General references

Hebrews 13:1
Let brotherly love continue.