In the Pentateuch, God appointed 7 “feasts” for the nation of Israel to celebrate annually.
In Lev. 23 – these are each called “CONVOCATIONS” – GATHERINGS
a. 3 A weekly sabbath
b. 4-8 Yearly Passover – 1st mo. Spring / Merged w/i 7 days of unleavened bread
c. 9-14 Yearly Firstfruits – 1st mo. Spring
d. 15-21 Yearly Weeks (Pentecost) – 50 days later @ harvest 3rd mo.
e. 23-25 Yearly Trumpets – 7th mo. Fall
f. 26-32 Day of Atonement – 7th mo. Fall
g. 33-36 Yearly Booths – 7th mo. Fall
In Jesus’ day – Weeks or Passover was associated with Moses having received the Law on Sinai about 50 days after the 1st Passover in Egypt.