The word Pentecost is from the Greek Pentekoste which means fifty. The LORD had instructed Moses to celebrate Shavuot fifty days after the waving of the sheaf offering during Passover (Leviticus 23:15-16). Although Shavuot began as a grain harvest festival, it is also celebrated as the time when the Torah (Instructions/Laws) was given on Mount Sinai.
As a newly redeemed people the LORD made a Covenant with Israel and gave them His Commandments and rulings to live by. He instructed Moses to cut two tablets of stones upon which he would write His Commandments. It was on Shavuot, fifty days after they left Egypt, that Moses received Torah.
It was not long after that Israel broke the Covenant. However, the LORD had promised of a time when He would make a New (renewed) Covenant with Israel. In Jeremiah 31:31-34 we read:
The days are coming,” declares the Lord, “when I will make a new covenant with the people of Israel and with the people of Judah. It will not be like the covenant I made with their ancestors when I took them by the hand to lead them out of Egypt... This is the covenant I will make with the people of Israel ... “I will put my law in their minds and write it on their hearts, I will be their God, and they will be my people."
How the LORD would later write His Torah on the hearts of His people is what is absolutely powerful about Shavuot/Pentecost
Fifteen hundred years after Mount Sinai, Jews from all over were gathered in Jerusalem to celebrate Shavuot. It had been fifty days since Yeshua's (Jesus) death, burial, resurrection and his ascension to heaven. The believers were gathered in a room, when suddenly there was the sound of a mighty rushing wind and the Holy Spirit descended like tongues of fire upon the believers. Was it coincidence that the Torah and the Holy Spirit were given on the same day at Shavuot? There is no coincidence with God. It was part of the fulfillment of the covenant promise made in Jeremiah 31.
In the Mosaic Covenant, Torah was written on stone tablets. Under the New Covenant this same Torah given at Mount Sinai is now in our minds and written on our hearts. How is that possible? The Holy Spirit. Writing Torah on the heart ensures its observance. It means that Torah is no longer external on stone tablets, but internal; it is who we become. This is one of the promises of the New Covenant.
If you are a believer in Yeshua, as you celebrate Pentecost Sunday, what a powerful truth to cherish.
"I will put my Spirit in you. I will enable you to live by my laws, and you will obey my rules."