Over at his blog Christianity in Antiquity, Bart Ehrman answers a reader's email about my monograph, Jesus' Literacy: Scribal Culture and the Teacher from Galilee (T&T Clark, 2011), a link to which is below. He speaks positively of the study (and my first book, which he and Eldon Epp published in their Brill series) and gives a useful overview of some of the pertinent issues surrounding this complex, interesting, and controversial issue. Bart and I are largely on the same page, as he notes, but he holds out some possibility for Jesus being able to read Hebrew. So much of this issue must remain unknown ultimately, but I think that's very unlikely. Ossuary inscriptions from the Second Temple period indicate that some level of familiarity of Hebrew existed even at the popular level. But knowing a few words and using them in a funerary context is a far cry from being able to read sophisticated scriptio continua Hebrew documents. Even in our own context, we wouldn't conclude from tombstones with Latin inscriptions that people in our culture can generally read Virgil's Aeneid, much less read it publicly. These types of literary skills--reading and writing and/or copying lengthy Hebrew texts (and remember that not everyone who could read could also write)--resided mainly among the scribal-elite circles who had the leisure time to pursue such an education. The vast majority of Second Temple Jews living off the land were illiterate, as they had no real use for literate skills and no time in which to acquire them. Bart rightly cites the influential works of William Harris and Catherine Hezser in this regard, who both show that there was nothing like a public education system that reached the majority of the populace. But even among the minority scribal elite who did receive an education, not all attained complete proficiency in reading Hebrew. One of the documents from the Qumran community, 4Q266, includes a statement that members were not allowed to read Torah publicly unless they could do so without having to "sound out" the words. And despite what many people say, there is absolutely no reliable evidence that reading and writing education occurred in synagogues in the first century. That is a projection of our own literate society onto the world of Jesus. There is no solid evidence that there was an elementary school in the synagogue at Nazareth, much less that Jesus attended it.
The New Testament showcases a disagreement between two Gospel authors as to whether Jesus resided in the scribal-literate class. I've published in great detail on this issue in Jesus' Literacy and Bart cites this important Gospel disagreement in his post. Mark 6.3 has Jesus rejected in the Nazareth synagogue as a teacher because he's a carpenter. Luke 4 also has Jesus rejected, but not because he's a carpenter. Luke even attributes public reading of the Scripture to Jesus. So Mark thinks Jesus is outside the scribal-literate class and Luke thinks he's inside it, though both agree that Nazareth wasn't the highlight of his teaching career in the eyes of his contemporaries. Interestingly, John 7.15 simply reports that one of Jesus' audiences was confused about his scribal-literate status. I've argued extensively in Jesus' Literacy that the most likely historical scenario is that Jesus did not hold scribal literacy, but that some of his contemporaries probably thought he did. This is the launching point also for my newest book, Jesus against the Scribal Elite.
Let me state two others things quite clearly. First, saying that Jesus could not read the Hebrew Scriptures is not the same as saying he did not know them. I think he clearly did know them, even intricately, but this type of knowledge acquisition was available through the public reading of Scripture in synagogue. Second, saying that Jesus was a scribal illiterate is not the same as saying he was stupid. This is another projection of our world onto the world of Jesus. Most people in industrialized societies today receive an elementary education. This simply was not the case in the ancient world and the vast majority (90% to 95% or even higher) were illiterate. If you're interested in these issues, here's a link to the paperback (and cheaper) edition of my book. If nothing else, I hope that Bart's discussion and this post indicate that the issue of Jesus' literacy is not simply a novelty topic. It relates directly to what type of teacher Jesus was and thus how he was received by his audiences (hostile and friendly). All the Gospels agree on that.