Divisions among Lutheran churches about the Bible and its teachings on homosexuality could affect one of the largest social service networks in the U.S. that runs programs ranging from adoption to disaster relief.

The theologically conservative Lutheran Church's Missouri Synod says it's becoming increasingly difficult to work with its liberal counterpart the Evangelical Lutheran Church in America, who in 2009 approved the ordaining of gays and lesbians.

Together, the two Lutheran denominations run social services nationwide.

In some communities, Lutheran Charities are some of the biggest service providers and have been struggling to meet increased demand for help during the recession.

One of the joint Lutheran agencies, Lutheran Services in America, said on its website that it encompasses more than 300 health and human services organizations with a combined annual budget of more than $16 billion.

"We recognize that this is a difficult issue. It's complicated," the Rev. Herb Mueller, first vice president of the Lutheran Church-Missouri Synod.

"We're trying to take a nuanced and caring approach to all of these situations that's also faithful to what the Bible teaches on these issues," he said.

The 2.3 million-member Missouri Synod has been studying the issue for more than a year through its Committee on Theology and Church Relations.

This week, the panel issued a 15-page document of guidelines for churches, congregants, and ministers on how they should decide whether to continue direct joint work with the Chicago-based Lutherans.

The conservative Lutherans announced this week that they will no longer train military chaplains with the ELCA.