“And it shall come to pass afterward, that I will pour out my Spirit on all flesh; your sons and your daughters shall prophesy, your old men shall dream dreams, and your young men shall see visions. Even on the male and female servants in those days I will pour out my Spirit.
“And I will show wonders in the heavens and on the earth, blood and fire and columns of smoke. The sun shall be turned to darkness, and the moon to blood, before the great and awesome day of the Lord comes. And it shall come to pass that everyone who calls on the name of the Lord shall be saved. For in Mount Zion and in Jerusalem there shall be those who escape, as the Lord has said, and among the survivors shall be those whom the Lord calls. (Joel 2:28-32 ESV)
This passage from Joel is quoted by Peter at Pentecost, as he explains how it is that the apostles speak in the tribal languages of the people gathered from across the world to celebrate the great annual feast in Jerusalem. This day has come. The wrath of God described in various ways by the prophets has come down fully upon Jesus, making way for cleansing and healing of the people of their sin. The Spirit of God is poured out in such a way that God dwells with us. This “great and awesome day of the Lord” is that day of the Lord’s crucifixion. It was a day in which the sun was blotted out and the moon rose already in eclipse so that be 3pm in the afternoon it was a “blood moon.” But what it means is the important thing, which is this: “everyone who calls on the name of the Lord shall be saved.” The way to God is open because Jesus came down to man.
Lord, since this way is open, will you guard my heart from neglecting it? Would you open the eyes of my children to see it? Will you grant me opportunities to tell of it?