In Deuteronomy 16:9, we read: "Count off seven weeks from the time you begin to put the sickle on the standing grain." Shavuot means weeks. For seven weeks, you have been harvesting. This is where you get the word "Pentecost" meaning "50 Days".
Sivan is the time to offer to GOD the "Korban Minkhah" or "grain offering" in addition of all other sacrificial and freewill offerings during the Feast of Weeks.
"Three times a year all your men must appear before the LORD at the place he will choose: At the Feast of Unleavened Bread, the Feast of Weeks and the Feast of Tabernacles. No man should appear before the LORD empty-handed (Deuteronomy 16:16)."
"In the third month after the Israelites left Egypt - on the very day - they came to the Desert Sinai (Exodus 19:1)." And the LORD said to Moses, "Go to the people and consecrate them today and tomorrow. Have them wash their clothes and be ready by the third day, because on that day the LORD will come down on Mount Sinai in the sight of all the people (Exodus 19: 10-11)."
"Now if you obey me fully and keep my covenant, then out of all nations you will be my treasured possession (Exodus 19:5). Ask GOD in your prayer this month to make you His treasure.
SIVAN: THE MONTH OF THE HOLY SPIRIT
SIVAN OFFERINGS: JESUS GRAIN OFFERING AND ALL SACRIFICIAL AND FREEWILL OFFERINGS
We know according to scripture the third month is the month of Sivan. We read: "At once the royal secretaries were summoned - on the twenty-third day of the third month, the month of Sivan..
They wrote out all Mordecai's orders to the Jews, and to the satraps, governors and nobles of the 127 provinces stretching from India to Cush (Esther 8:9)"
Lord Jesus House of Prayer