For a nation has come up against My land,
Strong, and without number;
His teeth are the teeth of a lion,
And he has the fangs of a fierce lion. Joel 1:5

Consecrate a fast,
Call a sacred assembly;
Gather the elders
And all the inhabitants of the land
Into the house of the Lord your God,
And cry out to the Lord.
Alas for the day!
For the day of the Lord is at hand;
It shall come as destruction from the Almighty. Joel 1:14,15

Blow the trumpet in Zion,
And sound an alarm in My holy mountain!
Let all the inhabitants of the land tremble;
For the day of the Lord is coming,
For it is at hand: A day of darkness and gloominess,
A day of clouds and thick darkness,
Like the morning clouds spread over the mountains.
A people come, great and strong,
The like of whom has never been;
Nor will there ever be any such after them,
Even for many successive generations. Joel 2:1-2

The Lord gives voice before His army,
For His camp is very great;
For strong is the One who executes His word.
For the day of the Lord is great and very terrible;
Who can endure it? Joel 2:11

Blow the trumpet in Zion,
Consecrate a fast,
Call a sacred assembly; Gather the people,
Sanctify the congregation,
Assemble the elders,
Gather the children and nursing babes;
Let the bridegroom go out from his chamber,
And the bride from her dressing room. Joel 2:15-16

…and a number other notable verses were looked at, including the title selection.