A week ago tomorrow, nearly two millennia ago, the Church was born. The Spirit of God fell upon a group of people of perhaps unprecedented size—and lived in them from then on—one of the last of a series of history-changing events in the space of less than a century.
Many centuries before, seven weeks after the first great divine deliverance (the Exodus), God assembled the twelve tribes at Mount Sinai and gave them the Law. God brought the people out of Egypt, and now gave them the Law, so that (one of the missionaries our church supports is fond of “hina clauses” like that) they might be his people and serve him, and that he might be their God. God’s people are to, as the Law says, “love the Lord their God, and to serve the Lord their God, and to walk in all his ways.”
But, as Joshua warned them (24:19), and their history from the giving of the Law onward made plain, having the Law was not sufficient for them to keep it, let alone do so naturally.
Therefore, after the Christ died and rose again so that out of every nation he might make “a people belonging to God”, and “that death may die”, on the very day commanded to celebrate the giving of the Law, God descended on his Church in the person of his Spirit—so that Joshua’s warning that “You are not able to serve the Lord” might no longer be true.
Without the Spirit, “every inclination of the thoughts of [man’s] heart [is] only evil all the time.” And while the Spirit had rested on some individuals (prophets) for extended periods before, he had never lived in them before. Before the coming of the Spirit on Pentecost, the Law and common grace restrained the evil “bent” of humanity; after it, through the Spirit’s ministry of the same power that raised the Christ from the dead, Christians become “regenerate” and begin to grow up into true life instead of walking inexorably in the paths of death inherited from Adam.
This is also the seal—deposit—down payment—of the assurance that “all God’s promises find their ‘Yes!’ in Christ.” Because we can see and experience the promises God made first through his prophets and then through his Son—that he would dwell with us, and that he would change our hearts to be inclined toward him rather than “bent” away—beginning to come true in our own lives, we can be even more certain that he will fulfill his remaining promises than we would be based merely on the historical fulfillments of his promises in the resurrection of the Christ and in his judgments on various nations (including those he had called his people, only a few decades after the events we celebrated this week and in Eastertide).
Thanks be to God!