1) The author of 'Acts' did not know about Josephus' Antiquities (published 93 CE) but was aware of Josephus' Wars (published 78 CE).
2) From this website: "With the agreement of nearly all scholars, Udo Schnelle writes, "the extensive linguistic and theological agreements and cross-references between the Gospel of Luke and the Acts indicate that both works derive from the same author" (The History and Theology of the New Testament Writings, p. 259)". See here for dating of gLuke.
3) There is external evidence about 'Acts' material in John's gospel, the later, as I already explained here, was completed (around 105 CE).
As demonstrated on my website:
A) The original gJohn itself was composed with the knowledge of gMark and not yet of gLuke.
The gospel ended then at Jn 20:10, after the 'empty tomb' segment (as in Mk 16:8, the original ending of gMark), when "... the disciples went away again to their own homes", as "prophesied" in Mk 14:27-28 (disciples dispersing in Galilee) & Jn 16:32 "... you will be scattered, each to his own home, and will leave Me alone".
B) Then, after gLuke got known, the gospel was added up and its ending was then pushed back to Jn 20:23, in order to include a brief post-mortem appearance to the disciples in Jerusalem (in contradiction with Jn 20:10 & 16:32!), similar to the one in Lk 24:36-49 right before the ascension (24:50-51).
C) Then, after 'Acts' appeared, gJohn was extended up to Jn 20:31, with a second post-mortem appearance to the disciples, one week later.
a) The impression given by Lk 24:36-49 is that the reappearance to the disciples was short. And immediatly after, Jesus (and company) goes towards Bethany and he ascends to heaven: no second reappearance possible one week later!
However in 'Acts', we have, and before the ascension occurs (again!):
Ac 1:3 "to whom [the apostles] He also presented Himself alive after His suffering by many infallible proofs, being seen by them during forty days and speaking of the things pertaining to the kingdom of God."
That would open the possibility for a second reappearance in gJohn to the disciples one week later!
b) Jn 20:30 "And truly Jesus did many other signs in the presence of His disciples ['disciples' for "John" means members of the twelve and other close followers/believers], which are not written in this book;"
Isn't it reminiscent of "presented ... many infallible proofs [to his "apostles" (1:2), during the forty days after his first reappearance]", from Ac 1:3, previously quoted?
Let's note also these latter signs are performed amidst the disciples only, not among other (unfriendly) Jews as before the crucifixion. Once again, this is very much according to:
Ac 10:40-41 "Him God raised up on the third day, and showed Him openly, not to all the people, but to witnesses chosen before by God, even to us [the eleven] ..."
Furthermore, at the same time, insertions were made according to what appears in 'Acts'.
a) Jn6:62 "[to his disciples] What then if you should see the Son of Man ascend where He was before [in heaven]?"
Here is a clear indication of the ascension (not mentioned in GMark & GMatthew).
In Lk24:50-53, it is not specified the disciples see the ascension, narrated briefly as "He was parted from them and carried up into heaven".
But in 'Acts', they do see it:
Ac1:9 "... they [the disciples] watched, He was taken up, and a cloud received Him out of their sight."
Furthermore, Jn6:62 appears to be an inserted digression, not related at all to the main topic.
b) Unlike Paul's letters, 'Hebrews', 'James', GMark, GLuke (but not GMatthew), 'Acts' features Jesus as the Judge:
Jn5:22 "For the Father judges no one, but has committed all judgment to the Son,"
Jn5:27 "[the Father] has given Him authority to execute judgment also, because He is the Son of Man."
Jn5:30 "... As I hear, I judge; and My judgment is righteous, ..."
However somewhere else, and somewhat conflicting:
Jn12:48 "He who rejects Me, and does not receive My words, has that which judges him; the word that I have spoken will judge him in the last day."
Here, it is not Jesus who will judge "in the last day", but "the word that I have spoken", suggesting Jn5:22-30 was written later.
Furthermore, it does not appear Jesus would be the Judge in this verse:
Jn8:50 "And I do not seek My own glory; there is One who seeks and judges"
It looks the change was due to:
Ac10:42 "... He [Jesus] who was ordained by God to be Judge of the living and the dead."
4) There is a potential external evidence in the epistle of Barnabas (dated 97 CE):
Barnabas 7:2 "... the Son of God, who is Lord all things, and who will judge the living and the dead ..."
which is very similar of:
Ac 10:42 "He [Jesus] who was ordained by God to be Judge of the living and the dead."
5) First, let's start here on the dating of the Epistula Apostolorum, from internal
16-17 Coptic version "... The wings of the clouds shall bear me in brightness, and the sign of the cross shall go before me, and I shall come upon earth to judge the quick and the dead.
We said unto him: Lord, after how many years shall this come to pass ? He said unto us: When the hundredth part and the twentieth part is fulfilled, between the Pentecost and the feast of unleavened bread, then shall the coming of my Father be"
This could not have been written after 150-156. That would have been stupid to claim that after the deadline went by and the big event did not happen.
And when the Ethiopic version was written, the 120 years after Pentecost got increased to 150 years.
In the Epistola Apostolorum, we have details which can only comes from 'Acts of the Apostles':
30-31 "But he [resurrected Jesus] said unto us: Go ye and preach unto the twelve tribes, and preach also unto the heathen, and to all the land of Israel ... And unto the others also will I give my power, that they may teach the residue of the peoples.
31 And behold a man shall meet you, whose name is Saul, which being interpreted is Paul: he is a Jew, circumcised according to the law, and he shall receive my voice from heaven with fear and terror and trembling. And his eyes shall be blinded, and by your hands by the sign of the cross shall they be protected. Do ye unto him all that I have done unto you. Deliver it (? the word of God) unto the other. And at the same time that man shall open his eyes and praise the Lord, even my Father which is in heaven."
Conclusion: The evidence may not be overwhelming for a dating of around 90 CE for 'Acts' due to the lack of timely unequivocal external evidence, but it is the most plausible. On my next post, I will show why the external evidence about Paul & 'Acts' up to 180 CE is not abundant. On the same post, I have another argument against a 2nd century dating of 'Acts'.