Considering the early Christian writings, I think it's reasonable to conclude that the Gospels were not published until c.150.
While I agree the Gospels were probably WRITTEN c.70 - c.100, their authors and origins are unknown, and they remained hidden and private. They were not available to other Christians until Justin Martyr had his hands on them c.150.
Here is the evidence - all the Christian writings from 70-160, by each decade (with a count for each decade) :
70s :
(First war with the Romans, Temple destroyed.)
G.Mark written.
80s (3) :
Colossians, 1 John, James.
G.Luke and G.Matthew written.
90s (5) :
Ephesians, 2 Thessalonians, 1 Peter, 1 Clement, Revelation.
G.John written.
100s (2) :
Didakhe, Jude.
110s (1) :
(115-7 Minor war with the Romans)
Barnabas.
120s (5) :
2 John, 3 John, Apocalypse of Peter, Secret James, Preaching of Peter.
130s (7) :
(132-5 Bar Kochbar major war with the Romans - Jerusalem, Judea, and the Jews are razed, erased and expelled.)
2 Peter, Titus, 1 Timothy, 2 Timothy, Hermas, Ignatius, Polycarp to Phillipians.
Papias knows rumours about Gospel-like writings.
140s (3) :
Mathetes to Diognetus, Epistle of the Apostles, 2 Clement.
150s (3) :
Ptolemy, Dialogue of the Saviour, Martyrdom of Polycarp.
Justin Martyr - first to have Gospels in hand c.150.
Summary -
29 books written from 70 to 160 do NOT show knowledge of written Gospels (counting Ignatius as one.)
Of course, not all of these books could necessarily be expected to mention the Gospels, but they are also silent on most historical details about Jesus Christ - e.g. Justin Martyr is the very first Christian writer on record to mention the Empty Tomb, or Nazareth, or the baptism in the Jordan river.
Being un-mentioned by any one of these 29 books is good evidence that the Gospels were unpublished and generally unknown to Christians during this time.
A comprehensive table showing early Christians citations of key words and phrases can be found here :
http://kapyong.info/ChristianTable.html
Possible Objections :
1 Clement.
Does not really quote the Gospels, but merely gave a few SAYINGS attributed to Jesus, which are SIMILAR to what's found in the Gospels. He DID quote scripture, and Paul, many times, often by name. My analysis of Clement is here :
http://kapyong.info/ClementRome.html
Barnabas.
Does not quote the Gospels, just has a phrase similar.
Polycarp to Phil.
Does not quote the Gospels, but has some similar phrases.
Ignatius.
He does know a few details of the story (e.g. the very first to mention Mary), and is the very first to claim Jesus Christ was historical. But he does not have any Gospels, nor mention any.
Papias.
According to Eusebius in the 4th century, Papias wrote in early-mid 2nd century that he had heard that :
- Mark had written down recollections of Peter, in Rome, but they weren't in order.
- Matthew had written down the Sayings of Jesus in Hebrew (probably meaning Aramaic)
These are rumours at best, a couple of decades before Justin Martyr got his hands on actual Gospels.
Someone Knew the Gospels
Yes, the authors knew them, and probably their immediate circle knew them. But they were hidden and unknown - NOT PUBLISHED.
Writers Didn't Mention What Everyone Knew
Ridiculous. How would readers ever learn anything new ? How would writers know what the readers knew ? Anyway - from Irenaeus on, writers like ClementAlex, Tertullian, Origen, and Hippolytus repeat the well-known Gospel details over and over. So do most Christians from then on, so do most Christians to this day - repeating and discussing the Gospel stories is a common favourite topic.
My conclusion is supported by the evidence - the Gospels were not PUBLISHED until c.150 with Justin Martyr the FIRST to have them.
Kapyong