'Day of the Lord' in the Bible

Alas for the day!For the day of the Lord is near,And it will come as destruction from the Almighty.

Blow a trumpet in Zion,And sound an alarm on My holy mountain!Let all the inhabitants of the land tremble,For the day of the Lord is coming;Surely it is near,

The Lord utters His voice before His army;Surely His camp is very great,For strong is he who carries out His word.The day of the Lord is indeed great and very awesome,And who can endure it?

“The sun will be turned into darknessAnd the moon into bloodBefore the great and awesome day of the Lord comes.

Multitudes, multitudes in the valley of decision!For the day of the Lord is near in the valley of decision.