For the vigil Mass.
Summary: The LORD promises to pour His Spirit on all people, showing signs in the sky and on earth. All who call on His name will be saved, and a remnant will remain in Jerusalem.
Thus says the LORD: I will pour out my spirit upon all flesh. Your sons and daughters shall prophesy, your old men shall dream dreams, your young men shall see visions; even upon the servants and the handmaids, in those days, I will pour out my spirit.
And I will work wonders in the heavens and on the earth—blood, fire, and columns of smoke. The sun will be turned to darkness, and the moon to blood, at the coming of the day of the LORD, the great and terrible day. Then everyone shall be rescued who calls on the name of the LORD; for on Mount Zion there shall be a remnant, as the LORD has said, and in Jerusalem survivors whom the LORD shall call.