'Day' in the Bible

I thank God, whom I serve with a clear conscience as my ancestors did, when I constantly remember you in my prayers night and day.

and that is why I suffer these things. But I am not ashamed, because I know the One I have believed in and am persuaded that He is able to guard what has been entrusted to me until that day.

May the Lord grant that he obtain mercy from Him on that day. And you know very well how much he ministered at Ephesus.

There is reserved for me in the future the crown of righteousness, which the Lord, the righteous Judge, will give me on that day, and not only to me, but to all those who have loved His appearing.