How many 1st to 2nd nonChristian writers who mentioned Christians described them as odd? How many did not? Peter Kirby writes:
If there is one impression that we can gather from the references to Christians in our non-Christian sources, one common theme that that runs through Tacitus, Suetonius, Pliny the Younger, Epictetus, Lucian, Marcus Aurelius, Galen, Celsus, and Philostratus, it is the inherent oddity they ascribe to the group. The only real exception in the literature of the era that stands out is that attributed to Mara Bar-Serapion... SOURCE:
http://peterkirby.com/mara-bar-serapion ... ntury.html
Certainly, some Christian teachings and practices could seem strange to a non-Christian, like the man Jesus being the Second Person of the Trinity or the Eucharist having Jesus' body and blood. Paul in one epistle said that the teaching of the crucified Messiah was "nonsense to the Greeks."
Out of the non-Christian writers who commented on Christianity, Thallus and Phlegon might have seen Christianity as odd, since they might have proposed a natural phenomenon for the darkness at the Passion. The rabbinical Council of Jamnia saw them as odd, since their Birkat Ha-Minim curses the heretics, and was aimed at Christians among them. The Talmud records hostile statements from Rabbi Akiva about Christians in the early 2nd century. Suetonius, Pliny the Younger, and Tacitus described Christians as having superstitio (excessive religiousity). Galen, Celsus, and Lucian criticized Christianity for superstition. Minucius Felix wrote that Fronto "scattered reproaches as a rhetorician". Seneca and his brother, the consul Gallo, might not have seen Christianity as odd, since Seneca referred respectfully referred to a crucified leader, who may have been Jesus. And Gallo let Paul go when charged by rabbis in Corinth. Pliny the Elder referred to the Nazerini in Syria in a straightforward way, as if they were well organized politically, and didn't mention anything odd. In his letter, Hardian says to punish Christians depending on their shamelessness.
Josephus most likely didn't consider them odd, since his passages on John the Baptist, Jesus, and James treat those figures respectfully. He writes that the Christians are still around at his time of writing, and doesn't directly state that they are odd. However, I believe that Josephus was actually a Christian. Epictetus praised Christians as an example of those who live a Stoic approach to persecution. He writes that just as crazy people might endure it by their madness, the Galileans endure it by "habit". However, I think that Epictetus might have been a Christian who syncretized his beliefs with Greek paganism. Mara Bar Serapion respected the Jews' wise king (perhaps Jesus) whom they killed. But he could have been a Christian. Kirby writes that Philostratus saw Christianity as odd, but Philostratus didn't directly mention it, and scholars debate whether his biography of Appollonius implies hostility to Christianity. Marcus Aurelius didn't characterize them as odd: His empire persecuted Christians on occasion, and in his Meditations, he criticized Christians for being ready to die out of their obstinacy. But "Eusebius says that Marcus wrote letters stating that in Germany his army was saved from thirst 'by the Christians’ prayers, and Marcus threatened to execute any who attempted to accuse us.'"(
http://www.seekingvirtueandwisdom.com/m ... istianity/) Trajan's reply to Pliny the Younger advises caution and restraint in suppressing them, and refers to the scenario of Christians not worshiping the Romans' gods, but doesn't say anything particularly weird about them.