'Day' in the Bible

For your fellowship in the gospel from the first day until now;

Being confident of this very thing, that he which hath begun a good work in you will perform it until the day of Jesus Christ:

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.

Circumcised the eighth day, of the stock of Israel, of the tribe of Benjamin, an Hebrew of the Hebrews; as touching the law, a Pharisee;