When the day of Pentecost came, they were all together in one place. Suddenly a sound like the blowing of a violent wind came from heaven and filled the whole house where they were sitting. They saw what seemed to be tongues of fire that separated and came to rest on each of them. All of them were filled with the Holy Spirit and began to speak in other tongues as the Spirit enabled them
God has raised this Jesus to life, and we are all witnesses of it. Exalted to the right hand of God, he has received from the Father the promised Holy Spirit and has poured out what you now see and hear.
Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins. And you will receive the gift of the Holy Spirit. (Acts 2)
Fifty days after the first Passover (on the first Pentecost) God first gave His commandments to His people Israel through His prophet Moses.
Fifty days after the Passover when Jesus was crucified, God first poured out His Spirit upon His people, those trusting in Jesus.
“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,
because they broke my covenant,
though I was a husband to them,
declares the Lord.
“This is the covenant I will make with the people of Israel
after that time,” declares the Lord.
“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. (Jer 31)
He has made us competent as ministers of a new covenant—not of the letter but of the Spirit; for the letter kills, but the Spirit gives life. (2 Cor: 3)