Exodus 34:22

And the festival of seven thou shalt make to thee, the first fruits of the harvest of wheat, and the festival of collection of the circuit of the year.

Exodus 23:16

And the festival of the harvest, the first fruits of thy works, which thou shalt sow in the field: and the festival of gathering in the going out of the year, in thy gathering thy works out of the field.

Numbers 28:16-31

And in the first month, in the fourteenth day to the month, a passover to Jehovah.

Numbers 29:12-39

And in the fifteenth day to the seventh month, a holy calling shall be to you: all work of service ye shall not do, and keep ye a festival to Jehovah seven days.

Deuteronomy 16:10-15

And do thou the festival of weeks to Jehovah thy God according to the willingness of thy hand which thou shalt give as Jehovah thy God shall bless thee.

John 7:2

And the festival of the Jews was near, the Pitching of tents.

Acts 2:1

And in the day of Pentecost being completed, they were all unanimously in one and the same place.

Treasury of Scripture Knowledge

Summary

And thou shalt observe the feast of weeks, of the firstfruits of wheat harvest, and the feast of ingathering at the year's end.

Bible References

Feast of weeks

Exodus 23:16
And the festival of the harvest, the first fruits of thy works, which thou shalt sow in the field: and the festival of gathering in the going out of the year, in thy gathering thy works out of the field.
Numbers 28:16
And in the first month, in the fourteenth day to the month, a passover to Jehovah.
Numbers 29:12
And in the fifteenth day to the seventh month, a holy calling shall be to you: all work of service ye shall not do, and keep ye a festival to Jehovah seven days.
Deuteronomy 16:10
And do thou the festival of weeks to Jehovah thy God according to the willingness of thy hand which thou shalt give as Jehovah thy God shall bless thee.
John 7:2
And the festival of the Jews was near, the Pitching of tents.
Acts 2:1
And in the day of Pentecost being completed, they were all unanimously in one and the same place.

General references

Exodus 23:14
Three times thou shalt keep a festival to me in the year.
Leviticus 23:15
And ye counted to you from the morrow of the Sabbath from the day ye brought the handful of lifting up; seven Sabbaths shall be complete.
Deuteronomy 16:9
Seven weeks shalt thou number to thee: from the beginning of the sickle upon the standing grain, thou shalt begin to number seven weeks.