Church groups flood the CA Supreme Court with written arguments for and against same-sex nuptials.

The legal battle over same-sex marriage in California is also a clash of religions.

As the state Supreme Court prepares for a three-hour hearing March 4 on the constitutionality of a state law allowing only opposite-sex couples to marry, the justices have been flooded with written arguments from advocates on both sides - including two large contingents of religious organizations with sharply differing views.

On one side are the Mormon church, the California Catholic Conference, the National Association of Evangelicals and the Union of Orthodox Jewish Congregations. They describe marriage between a man and a woman as "the lifeblood of community, society and the state" and say any attempt by the courts to change that would create "deep tensions between civil and religious understandings of that institution."

On the other side are the Unitarians, the United Church of Christ, the Union for Reform Judaism, the Soka Gakkai branch of Buddhism, and dissident groups of Mormons, Catholics and Muslims. Saying their faiths and a wide range of historical traditions honor same-sex unions, they argue that the current law puts the state's stamp of approval on "the religious orthodoxy of some sects concerning who may marry."

Those groups won't be represented at next month's oral arguments, when the court will hear from the parties in the case: same-sex couples and the city of San Francisco, challenging the marriage law, and the attorney general's and governor's offices, defending the law. Also participating will be lawyers seeking to intervene on behalf of two organizations opposing gay rights. Clash Over Gay Marriage