Unbelievers in Jesus often harp on the absence of evidence for Jesus outside of the New Testament. That’s like complaining that there’s no evidence against the accused except for all the evidence in the file on the accused. That is, such a complaint ignores the multiple and corroborated instances of evidence that have accumulated into a large file.
Nevertheless, there is evidence outside the New Testament that corroborates its account of Jesus. One example is the writings of Pliny the Younger (61-112 AD). In one of his many surviving letters, he wrote to the Emperor Trajan early in the 2nd Century A.D. about the many Christians he was encountering. That the movement would have generated enough adherents by this time is certainly consistent with the New Testament records. Moreover, Pliny’s most specific description of their beliefs and practice was that
“They were in the habit of meeting on a certain fixed day before it was light, when they sang in alternate verses a hymn to Christ, as to a god, and…”
Apart from viewing the New Testament account of Jesus’ life, death, resurrection, and ascension as an explanation, such a statement would be startling and inexplicable to any student of ancient history. Ancient Israel certainly expected a Christ, and some individuals actually claimed to be the Christ, but no group ever worshiped Christ as a god in heaven prior to what we see described in the New Testament.
It is even interesting to see how similar Pliny’s description is to the one we read from Athenian unbelievers in the New Testament’s book of The Acts of the Apostles:
“‘[This man Paul] seems to be a proclaimer of strange deities’- because he was preaching Jesus and the resurrection.” Acts 17:18
Pliny the Younger and other unbelieving Romans could not be expected to write accounts of Jesus and His followers until their numbers created a significant social movement that could not be ignored. And that is just what we see has happened. The question then remained, “What caused this social movement?” The account given by the New Testament documents is the only reasonable answer.