The Language of Jesus
It is the general consensus of religious scholars and historians that Jesus and his disciples primarily spoke Aramaic, the traditional language of Judea in the first century AD. Their Aramaic was most likely a Galilean accent distinct from that of Jerusalem. Jesus spent most of his time in the communities of Nazareth and Capernaum in Galilee, which were Aramaic-speaking villages. The Gospels support this view showing Jesus using various Aramaic terms: talitha koum (Mark 5:41); ephphatha (Mark 7:34); eloi eloi lama sabachthani (Matthew 27:46; Mark 15:34); abba (Mark 14:36). Historians, scientists, and social anthropologists largely agree that Aramaic was the prevalent language in Israel during Jesus’ time. Aramaic was very similar to Hebrew, but with many terms and expressions that were acquired from other languages and cultures, notably Babylonian.
Hebrew and Greek
Hebrew was used mostly by the scribes, teachers of the law, Pharisees, and Sadducees, the “religious elite.” Hebrew was likely spoken and read in the synagogues, so most people were likely capable to speak and understand some Hebrew. Because Greek was the language of the Romans, who ruled over Israel during Jesus’ time, Greek was the language of the political class and anyone who wanted to do commerce with the Romans. Being able to speak Greek was a very useful skill as it was the universal language at that time. However, some protested to use Greek because of hostility toward their Roman oppressors.
According to Dead Sea Scrolls archaeologist Yigael Yadin, Aramaic was the language of Hebrews until Simon Bar Kokhba's revolt. Yadin recognized the change from Aramaic to Hebrew in the texts he studied, which had been recorded during the period of the Bar Kokhba revolt. In his book, Yigael Yadin notes, "It is interesting that the earlier documents are written in Aramaic while the later ones are in Hebrew. Possibly the change was made by a special decree of Bar Kokhba who wanted to restore Hebrew as the official language of the state."
It is probable that Jesus knew the three common languages of the cultures around him during his life on Earth: Aramaic, Hebrew, and Greek. From this knowledge, it is likely that Jesus spoke in whichever of the three languages was most suitable to the people He was communicating with.