On what day was John in the Spirit?

Answer

"I was in the Spirit on the Lord's day." Rev. 1: 10.

Who is the Comforter, and what was He to do?
Whom did Christ say the Holy Spirit would glorify?
What, more than all else, proves the perpetuity and immutability of the law of God?
On what day did the Jews meet for worship?
In what was shown the first tangible evidence of this \"falling away\" from the truth of God?
What does the historian say of this legislation?
How long was Jerusalem to be trodden down of the Gentiles?

Questions & Answers are from the book Bible Readings for the Home Circle