My teacher says: The current Gospels are not reliable because they were written in Greek, whereas the language of Jesus and his followers was Aramaic. Christians don’t have manuscripts from 40 AD in Aramaic. Further, when Titus destroyed Jerusalem in 70 CE, his speech was translated from Roman to Aramaic. It means Greek/Latin was not a language of ordinary people. If Jesus were crucified in a clear manner, there would be no disagreement among early Christian sects like Cerinthians, Ebionites, etc. What is your thought?
First of all, it is true that Jesus spoke in Aramaic and that the gospels were written in Greek. This is because by the 60s AD, the common language of the Church was Greek. Aramaic was only spoken by a fairly small minority of Jewish Christians in Palestine. It was eye-witnesses such as Matthew and John who wrote the gospels, plus Mark and Luke who spoke to eye-witnesses. Both were fully fluent in Aramaic, of course, but also in Greek. There is literally no reason to imply that the gospels are unreliable from the fact that the eye-witnesses and those who spoke to the eye-witnesses wrote the gospels. It is true that the words of Jesus were in Aramaic, not Greek, and therefore the original gospels have Jesus’ words translated. But then again, I read the Bible in English. In fact, 99% of those who read the Bible read it in translation, but this does not make the original text unreliable. Not at all. When Titus destroyed Jerusalem in AD 70 he spoke to the people in Aramaic (according to Josephus, that is). This is because in Jerusalem the first language was Aramaic. However, by AD 70 the primary language spoken throughout the churches was Greek. By this time, the second language was Coptic (Egypt), not Aramaic, but Titus spoke to the Jews in Jerusalem in Aramaic. How does this impact the reliability of the Bible? This is a red herring argument.
Greek (but not Latin) was a common language in the Promised Land during the time of Jesus. In the Decapolis, the area east and south of Galilee, it was the main language. There were several cities in Galilee, such as Tiberias, where Greek (and perhaps Latin) were principal languages. Scholars generally agree that Jesus probably spoke at least rudimentary Greek, as he grew up in an area where Greek was a very common language (though not the main language). It may be somewhat analogous to the situation where I live in California, where perhaps 30-40% speak Spanish as either their first or their second language. The statement that Greek was not a common language of the common people is not true, though Latin was probably still fairly rare in Palestine in the first century.
There is NO DISAGREEMENT in the first several centuries about the crucifixion of Jesus. This is a straight-up lie. I do not know your source, but it is just plain bogus. Cerinthus may have been a heretic, and the Ebionites were as well, but even these heretics did not deny the crucifixion. Cerinthus did not deny that Pilate crucified the person known as Jesus of Nazareth. Neither did the Ebionites. To deny the reality that the Romans crucified Jesus in the first century would be to bring ridicule on that person or group, as all knew what had happened in Jerusalem under Pontius Pilate. Some Gnostics in the second century did say that Jesus was a mere spirit who occupied the body that was crucified by the Romans, but even the Gnostics did not deny that the crucifixion happened. Muslim attempts to deny the crucifixion are 100% guaranteed to fall flat. The crucifixion of the man known as Jesus of Nazareth is as solid an historical fact as any in the ancient world. Muslims should stop this hopeless attempt to pretend that the crucifixion did not happen.