Still waiting for evidence that anyone actually read the gospels in the first century. We hear all about how fast Christianity grew yet this evidence draws a blank.
I have already explained that the very fact they were copied so widely indicates they had to have been read. Your question shows that you don't know anything about textual stability or how texts survived at all.
As for early attestation that the gospels were read, we have:
I Clement (c. 95-6): Clement cites both the Old Testament and New (Matthew and Luke) using phrases like
he graphe legei. He also cites other traditions concerning Jesus, indicating the existence of traditions that are lost to us, but which existed in the first century (more evidence of oral traditions).
Ignatius of Antioch (died in the early second century, active in the first): Not only does Ignatius show an awareness of Paul, he also cites Jesus traditions, some of which are from Matthew and John. He also may have known Luke (see
Smyrn iii 1-2).
The Didache (either late first century or early 2nd): The didache quotes from Matthew, as well as other traditions.
Papias (active in 1st and 2nd century): speaks of three out of the four gospels, not to mention oral traditions concerning Jesus.
Epistle of Barnabas (probably early 2nd century, possibly earlier): the author was acquainted with the gospel of Matthew.
Polycarp of Smyrna (active 1st and early 2nd century): Has about 100 quotations from the NT.
Shepard of Hermas (either late 1st or early 2nd century): shows an awareness of John and at least one of the synoptics
In other words, there is plenty of evidence from other texts, in addition to the widespread copying of NT manuscripts (and we actually possess 2nd century pieces of the gospel texts), that the gospels were used widely from the beginning.
