'Day' in the Bible

But who can endure the day of His coming? And who will be able to stand when He appears? For He will be like a refiner’s fire and like cleansing lye.

“They will be Mine,” says the Lord of Hosts, “a special possession on the day I am preparing. I will have compassion on them as a man has compassion on his son who serves him.

“For indeed, the day is coming, burning like a furnace, when all the arrogant and everyone who commits wickedness will become stubble. The coming day will consume them,” says the Lord of Hosts, “not leaving them root or branches.

You will trample the wicked, for they will be ashes under the soles of your feet on the day I am preparing,” says the Lord of Hosts.

Look, I am going to send you Elijah the prophet before the great and awesome Day of the Lord comes.