Going from Jude to Revelation 1, also wondered about the following:

Revelation 1:10 I was in the Spirit on the Lord’s day, and heard behind me a great voice, as of a trumpet,

People have explained to me that the term, "the Lord’s day", is the same as, "the day of the Lord".

Yes, it is similar, but it is still different.

Even early church writers, before the council of Nicaea, mentioned the use of the term as referring to the first day of the week, in light of the resurrection, rather than the sabbath day.

A number of amillennial, and/or preterist, views, hold to an early writing of the book of Revelation, before the fall of Jerusalem, at the hands of the Romans, in 70 AD.

Whereas the millennial, and/or dispensational, views hold to the writing of Revelation closer to 95 AD.

Irenaeus, a disciple of Polycarp, who was a disciple of John, wrote that John penned Revelation while Domitian was emperor (c. 81AD to 96AD), according to Eusebius.

However, there is another reason for considering the late date of writing, compared to the writing before 70 AD.

Paul was the apostle to the Gentiles:

Romans 11:13 For I speak to you Gentiles, inasmuch as I am the apostle of the Gentiles, I magnify mine office:

And though the LORD used Peter, to open the door to the Gentiles, with Cornelius in Acts 10, the gospel of the circumcision was committed to Peter:

Galatians 2:7 But contrariwise, when they saw that the gospel of the uncircumcision was committed unto me, as the gospel of the circumcision was unto Peter;

  8 (For he that wrought effectually in Peter to the apostleship of the circumcision, the same was mighty in me toward the Gentiles:)

Then in line 9, James and John are included in being sent to the circumcision:

Galatians 2:9 And when James, Cephas, and John, who seemed to be pillars, perceived the grace that was given unto me, they gave to me and Barnabas the right hands of fellowship; that we should go unto the heathen, and they unto the circumcision.

Those holding to the early writing of Revelation, have it written at least 3½ years before the destruction of Jerusalem in 70 AD.

At that time, Paul was still alive, in prison in Rome, during which, he wrote the epistle to Ephesians.

In the book of Revelation, Jesus has John write to the angel of the church of Ephesus.

The early dating of Revelation would have both written for the Ephesians at about the same time.

Paul, the apostle to the Gentiles, started the church in Ephesus, while he spent about three years there.

On his way to Jerusalem, when he would be arrested, Paul called for the elders of the church in Ephesus, who came and met him, and he spoke with them before entering the ship.

Neither then, nor in the epistle to the Ephesians, nor to his second epistle to Timothy, who was the pastor/bishop in Ephesus at that time, did Paul mention what John wrote.

Paul did not mention that they had left their first love, nor that if they didn't repent, their candlestick would be removed, yet that is what John did write to them.

It doesn't make sense that both were written for the Ephesians at the same time.

Paul mentioned in Galatians 2:9, shown above, that like Peter was, James and John were to go unto the circumcision:

James 1:1 James, a servant of God and of the Lord Jesus Christ, to the twelve tribes which are scattered abroad, greeting.

But by 70 AD, apparently all of them, including Paul, were dead, or had been martyred, except the apostle John.

Jerusalem and the temple were destroyed, so, apparently, what was mentioned in Galatians 2:7-9, was no longer the issue, and John was no longer sent to the circumcision.

John himself, according to church history, moved to Ephesus and ministered there, until he was sent to Patmos.

But after being released from Patmos, he returned to Ephesus.

So there appears to be some difficulties with the teaching that John wrote for the church in Ephesus while Paul was still alive, and writing to the same church.

Also, that would have been while Paul was still the apostle to the Gentiles, and John sent to the circumcision.

No, that would have been confusing to the Ephesians, and neither Paul, nor John, mentioned the other writing for the same church at the same time.

But the later date appears to clear up these difficulties.

Then, by 95 AD, 25 years after the destruction of Jerusalem and the temple, more and more believers gathered together on the first day of the week, rather than on the sabbath.

Although, some early church Gentiles began to refer to the first day of the week as the sabbath, that they said had changed, Jewish Christians wouldn't have said that.

The term, the Lord's day, was a good choice for the first day of the week, since the seventh day is called the sabbath by the LORD, yet the believers were gathering on the first day.

Jewish Christians would not have called the first day of the week, the sabbath, but they could call it the Lord's day.

And that would appear to coincide with the early church's teaching about John's use of the term, the Lord's day, in Revelation 1:10.

I cannot be dogmatic about all this, since only what is written in the scriptures is the word of God.

Church history is not the word of God.

So, that is why Christians who believe in the early date, and the Christians who believe in the late date, are still brothers and sisters in Christ, and certainly not the opposition.

Later, when we're with Jesus, if he chooses to tell us when it was written, then, and only then, will we know for sure when it was written.

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