'Day' in the Bible

when he comes to be glorified by his saints and to be regarded with wonder on that day by all who have believed including you, because you believed our testimony.

not to be so quickly upset or alarmed when someone claims that we said, either by some spirit, conversation, or letter that the Day of the Lord has already come.

We did not eat anyone's food without paying for it. Instead, with toil and labor we worked night and day in order not to be a burden to any of you.