Yom HaBikkurim (The Feast of Firstfruits) 16th of Nisan
The Feast of Firstfruits was a celebration of the spring barley harvest. The Israelites were required to bring the first sheaf of the harvest (the first fruits), beginning in the month of Nisan, to the Temple as a wave offering.
Yeshua was resurrected on this day, the “Firstfruits” of the resurrection. The counting of the Omer (Sheaves) begins on this day and ends fifty days later on Shavuot (Pentecost).
Just as it says in 1 Corinthians 15:20, Yeshua’s resurrection on the Feast of Firstfruits promises future resurrections.