Verse by Verse: Revelation 1:9
Look at verse 9 of chapter one and there we read this, "I John who also am your brother and companion in tribulation and in the kingdom and patience of Jesus Christ was in the isle that is called Patmos for the word of God And for the testimony of Jesus Christ." Now here John tells us where he was when he got this vision of the revelation of Jesus Christ.
Now let me repeat that the day of the Lord is the age to come preceded by the tribulation period with all of its sufferings and darkness culminating in the heavens parting and Christ returning as king of kings and Lord of Lords. Now all that is the day of the Lord but the Lord's Day my friend, as it is here, is a different expression and I am persuaded that it means the first day of the week. That is that John was in the spirit on the Lord's Day when all the saints gathered together to remember the Lord. in all probability John was alone on that island but he remembered the first day of the week he remembered the Lord's day and in spirit he was with all believers gathered everywhere remembering the lord.
Revelation; Day of Jehovah;
Talbot, Louis T., "Verse by Verse: Revelation 1:9" (1959). 1950-1959. mp3 270.