It is widely believed that Jesus’ everyday language was Aramaic. Jews learned this language during their Babylonian captivity. Ancient inscriptions in Aramaic have been found over a vast area extending from Egypt to China.
The Interpreter’s Dictionary of the Bible tells us, “The dialect daily spoken by Jesus and the disciples was Galilean Aramaic, which, as is noted in Matt. 26:73, was recognizably different from the southern dialect spoken in and around Jerusalem. It was in this same Galilean dialect that the Aramaic of the Palestinian Talmud and the older Midrashim was written… (article “Aramaic,” Vol. 1, p. 186).
Some scholars claim that Greek was the common language of Jesus” day. It hard to be absolutely certain about what was the common tongue of an ancient civilization. The writings that archeologists find may not represent what was normally used by the common man.