Like the vast majority of Jews, Rabbi Dan Cohn-Sherbok does not believe Jesus was the messiah.

But he also believes that the traditional Jewish community needs to learn about the movement of messianic Judaism that embraces Jesus.

"It's always better to listen to people than to spit on them,'' said Cohn-Sherbok, a Reform rabbi and professor of Judaism at the University of Wales. "The Jewish community does spit on the messianics. That's terrible, really.''

Cohn-Sherbok is speaking this week at the annual international conference of the Union of Messianic Jewish Congregations, meeting at the Adam's Mark Hotel Downtown. The conference, which has attracted more than 800 people, ends Sunday.

The 55-year-old Cohn-Sherbok, a Colorado native, spent about eight years researching and writing the book Messianic Judaism: The First Study of Messianic Judaism by a Non-Adherent, which was published last month.

"The whole purpose of the book is to inform the Jewish community. . . . It doesn't mean they will embrace them or like them. But they should at least know who the messianics are,'' he said.

Traditional Judaism -- which has Orthodox, Conservative and Reform branches -- holds that the messiah has yet to come, and that the teachings of Hebrew Scripture, contained in the Bible's Old Testament, are God's word.

Messianic Jews believe that both the Old and New Testaments are God's word, and that Jesus, referred to by his Hebrew name Yeshua, is the promised messiah.

Traditional Jews consider the messianic movement to be unauthentic Judaism, Cohn-Sherbok said.

Rabbi Barney Kasdan of San Diego, Calif., president of the messianic union, said there have always been Jews who believe in Jesus.

The union, one of several messianic organizations, was founded in 1979 with 19 congregations and has grown to 90. Among those is Beth Messiah on the Northeast Side, the host congregation for the the conference.

There are more than 300 messianic congregations worldwide -- 200 of them in the United States, including six in Ohio, Kasdan said.

Congregations include both Jews and non-Jews but are primarily the latter. They celebrate traditional Jewish holy days such as Passover, Yom Kippur and Hanukkah.

Kasdan said Christmas, the celebration of Jesus' birth, and Easter, commemorating his resurrection from the dead, are not observed because "those very themes can be celebrated in the Jewish holy days.''

The movement is growing as people view Jesus in a new light, he said.

"Part of what's happened in the last few decades is we're finding that when we as Jews see Yeshua as a Jew and within his original Jewish context, the message makes a lot of sense,'' Kasdan said.

Howard Silverman, who leads Beth Messiah, said messianic Jews share much with traditional Jews.

"We have a common history, we have a common ancestry, we have a common understanding of who God is,'' he said.

Silverman added, "Our desire is to certainly identify and participate in the Jewish community, at the same time being true to who we are and what we believe.''

In the future, Cohn-Sherbok said, traditional Judaism will continue to react negatively to the messianic movement because it presents competition.

But messianic Judaism is "infused with a deep sense of spirituality. It's vibrant, charismatic,'' he said, and has something to offer traditional Jews.

"If I were to give my colleagues within the movement advice, I would say instead of criticizing messianic Judaism, come and see what goes on and learn from it. There's something to discover.''