Did Jesus Speak Hebrew?

I started Brad Young's Jesus and His Jewish Parables: Rediscovering the Roots of Jesus' Teachings.  In my latest reading, Brad Young defends the view that Jesus' spoken language was Hebrew.

I wrote a post a few months ago that touched on John Meier's discussion of the language that Jesus spoke.  Meier argued that Hebrew in Jesus' day was primarily literary, whereas Aramaic was the spoken language in Palestine.  Meier also contends that the existence of Targumim, Aramaic translations and elaborations of the Hebrew Bible, attest to the fact that most of the Jews spoke and understood Aramaic.

Young has a variety of responses to these sorts of arguments.  First of all, Young argues that the Targumim were later than the time of Jesus.  Second, Young notes that most of the documents of the Dead Sea Scrolls are in Hebrew, whereas only a few are in Aramaic.  After noting that the Manual of Discipline is in Hebrew, Young states that "It is hard to imagine that the sect would have written this treatise in a language that would be difficult for its initiates or members to understand even if the literary nature of the scroll makes it highly unlikely that it could accurately represent the spoken language of the people" (pages 40-41).  Third, against the claim that Hebrew was only a scholarly language, Young contends that the Hebrew Bar-Koseba letters indicate that even mundane concerns could be discussed in Hebrew.  Young offers other arguments as well.

What does Young do with the times when Jesus in the Gospels speaks Aramaic?  On page 52, he states that "Mark...seems to be interested to add color to his narrative by adding some Aramaic phrases."  I wish that Young clarified why Mark would do this.  Why would Mark choose to use the Aramaic language to add color to his narrative?

Moreover, while Young does well to note that many Targumim are late, there are some that are early, such as the Targumim in the Dead Sea Scrolls.

I think that Young does well to ask why Hebrew was so prominent in the time of Jesus, if few understood it.  Could nationalism be a reason for the use of Hebrew, the same way that some have argued that parts of the Book of Daniel were in Hebrew for nationalistic purposes?