The reading is from Acts of the Apostles 2:14-21

In those days, Peter, standing with the eleven, lifted up his voice and addressed them, "Men of Judea and all who dwell in Jerusalem, let this be known to you, and give ear to my words. For these men are not drunk, as you suppose, since it is only the third hour of the day; but this is what was spoken by the prophet Joel: 'And in the last days it shall be, God declares, that I will pour out my Spirit upon all flesh, and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams; yea, and on my menservants and my maid servants in those days I will pour out my Spirit; and they shall prophesy. And I will show wonders in the heaven above and signs on the earth beneath, blood, and fire, and vapor of smoke; the sun shall be turned into darkness and the moon into blood, before the day of the Lord comes, the great and manifest day. And it shall be that whoever calls on the name of the Lord shall be saved.'"