Let me first of all put the question back to you.
Given that we are agreed that there is only one Coming of Christ as a thief taught in the Scripture, how did Christ come upon Sardis as a thief in AD 70? It is a pretty long way from Jerusalem.
The persecutions that those churches faced were led by the Jews (as we see with the Thessalonican persecution at Acts 17:5-8). When these evil men were destroyed in Jerusalem at AD 70, the churches gained relief. The Jews had been urging the Romans to persecute the Christians. The destruction of Jerusalem eliminated nearly all the non-Christ-following Jews of the entire Roman Empire, and Christianity emerged victorious.
The faithful and the unfaithful of the Asia Minor churches were to each receive something at His coming to them, each according to their works:
CHRIST'S JUDGMENT OF THE ASIA MINOR CHURCHES ACCORDING TO THEIR WORKS:
(*) I know your works...repent else I will come unto thee quickly and remove thy candlestick...but...To him that overcometh will I give to eat of the tree of life (Rev 2:5,7)
(*) I know your works...Repent or else I will come unto thee quickly and fight against them with the sword of my mouth....To him that overcometh will I give to eat of the hidden manna (Rev 2:16-17)
(*) I know your works... And I gave her [the Prophetess of Thyatira] space to repent of her fornication; and she repented not. Behold, I will cast her into a bed, and them that commit adultery with her into great tribulation, except they repent of their deeds. And I will kill her children with death; and all the churches shall know that I am he which searcheth the reins and hearts, and I will give unto every one of you according to your works. But unto you I say, and unto the rest in Thyatira...that which ye have already hold fast till I come...I will give him the morning star. (Rev 2:21-25,28)
Note that Jesus explicitly says that the Thyatria Prophetess movement chose not to repent, and that
he was coming and would kill her and her "children." But to the rest at Thyatria (the faithful), they were to hold fast and had no additional burden placed upon them, for Jesus had rewards to give them as stated in Rev 2:26-28. We know that Christ came to them, for he came and killed the Prophetess and rewarded the faithful as he said.
(*) I know your works...Remember therefore how thou hast received and heard, and hold fast, and repent. If therefore thou shalt not watch I will come on thee as a thief, and thou shalt not know what hour I will come upon thee. Thou hast a few names even in Sardis which have not defiled their garments; and they shall walk with me in white: for they are worthy. He that overcometh, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels. (Rev 3:3-5)
(*) I know your works...I am coming quickly; hold fast what you have, so that no one will take your crown. He who overcomes, I will make him a pillar in the temple of My God (Rev 3:11-12).
(*) I know your works, that you are neither cold nor hot; I wish that you were cold or hot. So because you are lukewarm, and neither hot nor cold, I will spit you out of My mouth....I stand at the door and knock; if anyone hears My voice and opens the door, I will come in to him and will dine with him, and he with Me. He who overcomes, I will grant to him to sit down with Me on My throne, as I also overcame and sat down with My Father on His throne. (Rev 3:15,20-21)
As everyone can plainly see,
Revelation 2-3 is Christ's judgment, the judgment at Christ's coming. The punishments and/or rewards received were based "according to their works," as was predicted in the gospels and epistles:
Matthew 16:27
For the Son of man shall come in the glory of his Father with his angels; and
then he shall reward every man according to his works.
Romans 2:5-8
thy hardness and impenitent heart treasurest up unto thyself wrath against the day of wrath and revelation of the righteous judgment of God,
Who will render to every man according to his works: To them who by patient continuance in well doing seek for glory and honour and immortality, eternal life: But unto them that are contentious, and do not obey the truth, but obey unrighteousness, indignation and wrath
This is all first-century stuff here. No "Church Age," no "1948," no "21st century computer chips" -- the glorified Jesus knew of none of those modern speculative doctrines, and that makes them impossible doctrines, ones not found anywhere in scripture. Had any of those things been biblical doctrines, then Jesus would not be speaking to first-century churches about His second coming in
Revelation 2-3 as we see Him doing.
All Christians of all ages need to watch and pray, and 1st Century Sardis was no exception.
How can that be true?
There is an explicit warning of what would happen to those who did not watch... was Jesus speaking empty threats?
How can every generation watch for an event ordained to take place only once in History?
What happened to the Christian from say, 1860, who "Watched for His coming" that was different from his christain neighbor who did not watch for it? Did they not Both Die in Christ?