JERUSALEM — Most Israeli Jews marry within their own religious or secular subgroups and inhabit largely separate social worlds, according to the findings of a new survey exposing the deep gulfs over the role of religion in Israeli politics and society.

The first in-depth study of religion in Israel conducted by the Pew Research Center in Washington, released on Tuesday, found that religious and social divisions are reflected in “starkly contrasting positions on many public policy questions,” and in profoundly differing attitudes toward the character of Israel.

So while 89 percent of Israel’s secular Jews, who make up 40 percent of the population, think democratic principles should take precedence over Jewish law on issues where the two collide, 89 percent of Israel’s ultra-Orthodox Jews, a smaller but fast-growing group, think the opposite.

The study found substantial differences among Israeli Jews on crucial questions. Even among self-identified centrists, opinion was split three ways on the issue of Israeli settlements in the occupied West Bank. Over all, a third believed the settlements hurt Israel’s security, a third thought they helped security and the remainder said they made no difference.