Why did Jesus use a Greek proverb when He spoke Aramaic to Saul in Acts 26:14? Saul spoke Greek, Aramaic, Hebrew, and Latin (there are many references). Jesus spoke Aramaic, Greek, and Hebrew (again there are many references). In Acts 26:14, Paul (who at this time was using his second name Paul, being a Roman, rather than his first name Saul), testified to Agrippa, possibly in Greek, that when Jesus confronted him on the road to Damascus, Jesus spoke to him in Aramaic and said, "It is hard for thee to kick against the pricks" (KJV), or "it is hard for thee to kick against the goad" (in other versions), which is a Greek proverb.

Is there any significance or relevance here of Jesus speaking in Aramaic and using a Greek proverb to Saul (who became Paul later on), who spoke four languages?
Acts 25:14, "it is hard for thee to kick against the pricks," is a direct quotation from a play by Euripides (d. 406 BCE), the Bacchae, with Jesus speaking instead of the Greek god Dionysus. Euripides had used the plural ('pricks') for reason of meter, and Acts uses the same plural, although it would normally be a singular. In his own epistles, Paul never mentions a conversion on the road to Damascus; in fact he said that after "it pleased God to reveal his son in me," he conferred with no one but went immediately to Arabia (Galatians 1:16-17). So, this was a literary elaboration by the author of Acts, ostentatiously saying that Jesus spoke in Aramaic probably to draw some attention away from the popular Greek saying.

Uta Ranke-Heinemann says, in Putting Away Childish Things, page 163, the really strange thing is that with both Jesus and Euripides we have the same “familiar quotation” and the same situation. In both cases there is a conversation between a persecuted god and his persecutor.  In the Bacchae the persecuted god is Dionysus and his persecutor is Pentheus, king of Thebes.  Just like Jesus, Dionysus calls his persecutor to account, “You  disregard my words of warning . . . and kick against the pricks a man defying god.” She says Jesus even uses the same plural form of the noun kentra ('pricks') that Euripides needs for the meter of his line. 

To eliminate any doubt that this is just a coincidence, we can also look at Acts' story of Paul's release from prison (Acts 16:26).  This also has reasonably close parallels to words in the same ancient play, the Bacchae, and there is no written or archaeological record of an earthquake powerful enough to have somehow released Paul and Silas from their chains. 

Peter Kirby notes the parallels between the Bacchae and Acts, but says that the author of Acts need not necessarily have had the Bacchae in mind, since other ancient Greek works use similar phraseology and would also serve as sources for these two scenes in Acts. The Bacchae stands out as a single source that provides the potential source material for both the conversion (with the plural form of kentra) and the prison escape in Acts.