Pentecost marks 50 days after Passover, where the Spirit of God descended upon Sinai to tell this soon-to-be-formed People of God the purpose for which they had been set free from slavery. They were set free so that they could hear God's voice, keep his commands, be his treasured possession, for the purpose of reclaiming the whole Earth as God's own (Exodus 19:4-6). For Israel, this meant keeping the Covenant: loving God, walking in his ways, and celebrating the entirety of the gift of the Torah (Deut 30:16). By doing this, Israel chose to live an abundant life in the land promised to Abraham for the purpose of blessing all the peoples of the Earth (Genesis 12:3).
Christians are most familiar with Pentecost being a New Testament event, which is true, but it is less than half of the story. Acts 2 records the commissioning of the Christian Church in terms very similar to the Exodus account of the first Pentecost. 50 days after the Passover/First Easter weekend, the Spirit of God again descended upon the soon-to-be-expanded People of God as a violent storm of fire, filling the entire place for all present to see. The grace of the Torah was expanded to not only be instructions given from the mouth of God to the People of God but became the essence of the people--the very words the apostles spoke were the very words of the Spirit of God. (Acts 2:2-3).
The fulfillment of the Passover was restated, echoing the covenant preamble of God stating that Israel had seen what He had done to fulfill the Passover already (2:14-36). The invitation was given to those present to cleanse themselves with the authority given to them by Christ's Passover (2:37-40). Rather than turning away in dread-fear as Israel had done at Sinai, the people accepted this newly stated covenant, remaining in awe and wonder (a different kind of fear) at God's marvelous works performed by those who He had sent out (2:41-43).
Today marks the day of the formation of the People of God. What it means to be the people of God has not changed. Our identity as the People of God requires us to realize that it is nothing that we have done that has earned us the right to be called People of God. Rather it is God's Nature of being compassionate, gracious, patient, loving, faithful, and merciful that prompts God to offer an abundant way of life to us (Ex 34:6). This new way of life is a free gift, but it is a gift that costs us everything, as it requires us to choose to pursue the best interest of God above all else, and to make the needs of our fellow men an equal priority to our own.
Pentecost is not about God initiating a paved road for people to go to Heaven. Pentecost is about the People of God accepting that God has paved a road for God to incarnate Himself today through the Church as the Body of Christ. The Spirit of God descended upon Sinai in Exodus 19 and was rejected out of fear. The Spirit of God descended upon Jerusalem in Acts 2 and was embraced in wonder.
I set before you today life or death, prosperity or adversity. Love YHWH your God, walk in His ways, and keep His Torah so that you might live and live abundantly, and that YHWH your God may bless you in any land you enter. Choose life, in order that you might live, loving YHWH your God, obeying His voice, and clinging tightly to Him; for this is the very source and sustenance of your life.