'Day of Christ' in the Bible

the true character of each individual's work will become manifest. For the day of Christ will disclose it, because that day is soon to come upon us clothed in fire, and as for the quality of every one's work-- the fire is the thing which will test it.

convinced of this same [thing], that the one who began a good work in you will finish [it] until the day of Christ Jesus,

That ye may approve things that are excellent; that ye may be sincere and without offence till the day of Christ;

Holding forth the word of life; that I may rejoice in the day of Christ, that I have not run in vain, neither laboured in vain.

That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.

not neglecting--as some habitually do--to meet together, but encouraging one another, and doing this all the more since you can see the day of Christ approaching.