But he may also have been trained as a Pharisee, part of the very group portrayed in the Christian gospels as a byword for religious hypocrisy. And some of Jesus' teachings were not as revolutionary as they appeared: contemporary rabbis taught the "golden rule" and other ideals found in the gospels.
Such ideas came as a surprise to about 50 Catholic religious educators who gathered for a recent workshop here, where they explored the Jewish roots of the Christian faith.
The "Christians and Jews Together" project aims to help Catholic educators pass on to their students a more nuanced appreciation of Christianity's Jewish roots. The Roman Catholic Archdiocese of Boston and the local Anti-Defamation League are sponsoring the program.
"The blatant misunderstandings have been addressed for some years now," said Celia Sirois, an instructor in scripture for the archdiocese.
She noted that since the Second Vatican Council renounced anti-Semitism in the 1965 document "Nostra Aetate," Catholics have purged their lessons of any hint the Jews are collectively guilty of murdering Christ or that God has rejected Judaism.
No one at the workshop, for example, found it challenging to imagine Jesus as a Jew, a notion that past generations de-emphasized or denied.
But, Sirois added, Catholics often lack detailed information about the Judaism of Jesus' day and of their own. For example, while Christians traditionally viewed the Hebrew Bible, known to Christians as the Old Testament, as an overture to the coming of Jesus, "the Jewish Scriptures have a permanent value quite apart from the Christian interpretation of them," Sirois said.
And the Pharisees, depicted so negatively in the gospels, included many genuine religious reformers.
"It is our responsibility to teach the next generation how to say who they are as Christians," Sirois told her fellow Catholic religious educators at the workshop. "They can't do that without knowing the roots of Christianity in Judaism."
Sirois and Naomi Towvim, a consultant with the regional Bureau of Jewish Education, have been teaching Catholic religious educators in the Boston area for the past five years. They have become so well-versed in each others' faiths, Sirois said, that "we have had people ask us, `Which one of you is Jewish and which one is Catholic?'"
Gail Barbato, a catechism teacher from the town of Framingham, said Catholic children in this ethnically mixed region need to know more about the faith of their Jewish friends.
"They go to school together, they play sports together, there's no reason why they shouldn't learn about each others' religions," she said.
The workshops include short lessons and small-group discussions led by Catholic and Jewish facilitators. Most teachers attend only one session--hardly a full education, but something to alert them to the subtleties of teaching about Judaism. In one discussion, for example, Catholics were surprised to hear that many Jews believe their scriptures do not foretell a messiah--Jesus or anybody else--but rather a figurative, better "messianic age" to come.
She noted, for example, that Jesus' near contemporary, Rabbi Hillel, summarized the law of Moses in words familiar to any Christian: "What is hateful to yourself, do to no other."
"Jesus is not unique in saying, `Love one another,' but there is a certain authority in the way he says, `As I love you,"' Sirois said. The challenge is to honor both "his humanity and his special status as the son of God."
Participants received a booklet explicating some of the thorniest passages in Scripture, using modern scholarship techniques that analyze the late-first century context in which the gospels were written.
For example, the Gospel of Matthew recounts Jesus' parable of a vineyard owner whose tenants rebel and kill his son, provoking the owner's retaliation. This passage, long cited by anti-Semites to prove God rejected the Jews because they rejected Christ, is too potent to teach to younger children, the booklet says. Teachers should tell older students that Matthew was interpreting Jesus' parables in light of a conflict between the Jewish establishment and the early church, the booklet says.
Since the church itself was still largely Jewish, the scriptures were not condemning Jews collectively.
So far, the workshops have been oriented toward Catholic rather than Jewish religious educators. The reason, Sirois said, is partly pragmatic.
"Catholics have a hierarchical structure in place, so it's easier to get something going," Sirois said.
The less-centralized Jewish educational institutions will have to be approached individually. But the two groups' motivations also vary, Towvim noted. While Christianity is incomprehensible without understanding its Jewish roots, Judaism developed independently of Christianity. And synagogue schools have only a few hours per week to teach an ambitious curriculum of Jewish religion and culture.
"It's a vague interest because they live in a Christian world, but given that they have so much on their plate, they don't perceive it as a necessary piece of teaching about Judaism," said Towvim.
Jewish volunteers in the program say they welcome the challenge of studying Christianity. "I have a lot of respect for Christians to open up their preconceived prejudices," said Janet Buchwald, a Jewish religious educator from the town of Sudbury and a facilitator at the workshops. "I'm looking forward to sitting at the other end of the table."