As a general rule, Jesus is not a particularly well-understood figure in Judaism. Since the topic dovetailed with my undergrad thesis, I spent lots of time examining Jewish attitudes towards Jesus in college-- ranging from the medieval polemic Toldot Yeshu, to philosophers like Profiat Duran, Jacob Emden and Moses Mendelssohn. I also looked at Enlightenment and Reform thinkers like Graetz, Geiger, Kohler, and the rabbis Wise (I.M. and Steven), as well as Yiddish modernists like Melech Ravitch, Itzig Manger, Peretz Markish, Abraham Sutzkever, Lamed Shapiro, Zalman Schneour, H. Leivick, Sholem Asch, and even Uri-Zvi Greenberg, all of whom incorporated depictions of Jesus into their writing at various points.
So when I hear that Shmuley Boteach has a book coming out about how Jews should relate to Jesus, forgive me if I'm a little skeptical already.
It's not that the topic should be off-limits. It's that Shmuley is neither a scholar, nor a historian, nor, indeed, even a philosopher. He is a salesman, a popularizer. These things can be fine, but when the "products" you decide to sell are people's deeply-held beliefs, it can lead to a volatile mix-- just ask Sholem Asch, who got tossed out of the Yiddish canon for his series of Christian novels. This is also not helped by the fact that Shmuley is one of the Jewish world's most self-aggrandizing and least humble personalities (also like Asch!), a man who never met a media outlet he didn't like, and who can't write an op-ed without either name-dropping a celebrity friend he hangs out with or trying to sell his new book, TV show, or half-eaten sandwich.
Simply put, Shmuley is not the right person to try to market Jesus' Jewishness. And all the more so since he apparently knows very little about the field he is purporting to comment on. As fellow Judeoblogger Izgad points out, there has been a ton of scholarship on "the historical Jesus" over the past 100-plus years, from both Jews and Christians. And unless new material is discovered, at this point it's frankly rather hard to draw any new conclusions about Jesus' identity or ideology without just making stuff up. The Gospel accounts are often vague or contradictory, and their value as reliable evidence is already questionable. Shmuley mines Haym Macoby at length and casts Jesus as a patriotic Pharisee, but it's not the only conclusion one can draw. One early Reform intellectual, I.M. Jost, saw Jesus as a brilliant man trapped by Pharisee culture, which he secretly despised. Heinrich Graetz, by contrast, thought Jesus was an Essene operating on the fringes of rabbinic Judaism. (Most Reform thinkers followed Abraham Geiger's idea that Jesus was a principled Pharisee fighting Sadducee literalism and corruption, a theme echoed by Asch in his novels.)
Frankly, the Gospels are just not all that clear. You can read Jesus any way you want to and find textual evidence for it-- that's part of the reason why there are so many Christian denominations in the world. One quick example is Jesus' Sermon on the Mount. In it, he says that he has not come to abolish the law-- and this claim is backed up within the sermon, as he procedes to create various fences around the Torah, just like the Pharisees did. On the topics of murder, adultery, oaths, and divorce, his pronouncements are far stricter than the Biblical prohibitions or rabbinic interpretations of the day. But at the same time, some of his reformulations of other themes are either more liberal than standard Pharisee teachings (kashrut being one good example), or so radically reformulated that they can't really be compared (loving your enemy and an eye for an eye come to mind). And elsewhere in the Gospels, we see Jesus doing various things that are clearly at odds with Jewish law, such as violating the Sabbath to pick food. He doesn't really justify himself there or clarify why he's doing it, he just does it.
When you look at his actions, the conclusion seems to be that when it comes to Jewish law, Jesus is (by Pharisee standards) inconsistent. Some things are very important, and some things aren't important at all. Does that make him beyond the pale of Judaism for his time period? I'm not knowledgable enough about second Temple-era Judaism to comment, but I sure do wish that when talking about the "historical Jesus" more people would take the time to read what the Gospels say he did and said, as well as get historical context about the mileu he lived in, so they can understand what was and wasn't controversial about what he was doing, instead of reading him through historical prisms from 2000 years later.
And this leads us back to Shmuley. At the end of the day, though I would prefer Shmuley stop writing books altogether, and certainly about topics as dicey as these, I find it absolutely laughable that segments of the Orthodox community sees Kosher Jesus as such a threat that they are banning people from reading it or wringing their hands that now evangelicals will think they've got a rabbi on their side. Evangelicals have been pushing Jesus on us long before Shmuley and if they're expecting an uptick in saved souls thanks to this book, I think they'll be disappointed. Besides, Shmuley lives for publicity and it's a particularly bad move to give him any excuse to claim his new "groundbreaking" book is making him the target of persecution. If you're going to talk about his book, talk about why it's either bad scholarship or extremely obvious marketing pandering.
At the end of the day, the Jewish community have to figure out what it is they don't like about Shmuley and his book. If it's that it's a crappy book, and that there are much better-- and substantive-- things to say about the topic, that's one thing. If it's that they're personally not interested in it, that's fine too. But if part of the backlash to this is that they're worried people are going to convert over it, I would say calm down and give your fellow Jews some credit. Even if that was his goal (and it's clearly not), Shmuley simply isn't that good a writer.
If people are interested in getting a more scholarly Jewish view of Jesus, or of actually "building bridges" between Jews and Christians like Shmuley says he is, one good resource to check out might be this book. I haven't read it yet, but I'm intrigued. God knows it's got to be better than Kosher Jesus.